This could be a long shot, but I'm hoping to experiment with OpenVMS
clustering using a shared system disk over fibre channel.

My two VMS systems are Integrity rx1600s. I'm trying to use a system
running FreeBSD as the target. After much experimentation and
troubleshooting, I've gotten pretty far, but the volumes are still stuck
"offline" in OpenVMS.

I just got the latest hobbyist kit from VSI and installed a fresh copy
of OpenVMS IA64 V8.4-2L3 on the server's internal hard drive.

In the two rx1600 servers, I'm using fibre channel HBAs with the QLogic
QLA2342 chip. From the EFI shell I've installed the latest EFI driver
and RISC firmware I could find:

<https://support.hpe.com/connect/s/softwaredetails?language=en_US&softwa
reId=ux_36358_2>

The card appears to be working properly from OpenVMS:

$ show dev /full fga0

Device FGA0:, device type QLogic ISP23xx FibreChannel, is online, shareable,
error logging is enabled.

Error count 0 Operations completed 12
Owner process "" Owner UIC [SYSTEM]
Owner process ID 00000000 Dev Prot S:RWPL,O:RWPL,G,W
Reference count 0 Default buffer size 0
Current preferred CPU Id 1 Fastpath 1
Current Interrupt CPU Id 1
FC Port Name 2100-00E0-8B09-B261 FC Node Name 2100-00E0-8B09-B261

I've been able to set up the target LUNs in FreeBSD with the "device-id"
option, which seems to satisfy OpenVMS's need for the UDID value; e.g.
if I set the device-id to 0x00000001, the device shows up as $1$DGA1 in
VMS, if I set it so 0x00000002, it shows up as $1$DGA2, etc.

The two LUNs appears as follows:

$ show dev dga

Device Device Error Volume Free Trans Mnt
Name Status Count Label Blocks Count Cnt
$1$DGA1: (IVMS1) Offline 1
$1$DGA2: (IVMS1) Offline 1

Or one of them in more detail:

$ show dev /full dga1

Disk $1$DGA1: (IVMS1), device type unknown, is offline, file-oriented device,
shareable, available to cluster, error logging is enabled.

Error count 1 Operations completed 0
Owner process "" Owner UIC [SYSTEM]
Owner process ID 00000000 Dev Prot S:RWPL,O:RWPL,G:R,W
Reference count 0 Default buffer size 512
WWID 01000010:6008-05F3-0012-00F0-0000-0000-0375-0000
Allocation class 1

So VMS knows the LUNs are there, but something still seems to be missing
to make VMS happy, and the devices just stay "Offline" with 1 in the
Error Count.

For lack of knowing what else to do, I ended up "faking" MSA1000
volumes, in case VMS was sensitive to particular devices. But I don't
think VMS really cares what the devices identify themselves as.

In any case, SYS$ETC:FIBRE_SCAN doesn't reveal any errors or problems.
The target and LUNs show up as I'd expect:

$ run sys$etc:fibre_scan
[...]
Probing Target 1 ==========================================================

Port WWID: 5001-4380-28CC-9A38
Node WWID: 5001-4380-28CC-9A38

Target = 1. LUN = 0.
----------------------
Devname: $1$DGA1:
Vendor ID: COMPAQ
Product ID: MSA1000 VOLUME
Devtype: 0 (Disk)
Rev Level: 4.32
WWID: 01000010:6008-05F3-0012-00F0-0000-0000-0375-0000

Reported LUN count = 2. at target 1.

Target = 1. LUN = 1.
----------------------
Devname: $1$DGA2:
Vendor ID: COMPAQ
Product ID: MSA1000 VOLUME
Devtype: 0 (Disk)
Rev Level: 4.32
WWID: 01000010:6008-05F3-0012-00F0-0000-0000-0375-0001
[...]

Here's an example of how I have one of the LUNs configure on the FreeBSD
side. Mostly made-up/faked values for the serial, vendor, product,
revision, just based on some working system in the wild in case there is
anything magical about needing to be a "COMPAQ" vendor or something. The
ident_info seems to be the magic that maps to UDID:

lun 0 {
backend block
device-id "600805f3001200f00000000003750000"
serial "MGKSERIAL0000"
option vendor "COMPAQ"
option product "MSA1000 VOLUME"
option revision "4.32"
option scsiname "0001"
option ident_info 0x00000001
option naa 600805f3001200f00000000003750000
path /dev/zvol/zroot/fc/vms00
}

Obviously this isn't a supported configuration by any means, but I'm
wondering if anyone has gone down this path before, or has any hints as
to determine what the error is, or if there's anything in the above
setup that looks like it might cause a problem?

Thanks,
Matthew

On 04/24/22 07:18, Matthew R. Wilson wrote:
> This could be a long shot, but I'm hoping to experiment with OpenVMS
> clustering using a shared system disk over fibre channel.
>
> My two VMS systems are Integrity rx1600s. I'm trying to use a system
> running FreeBSD as the target. After much experimentation and
> troubleshooting, I've gotten pretty far, but the volumes are still stuck
> "offline" in OpenVMS.
>
> I just got the latest hobbyist kit from VSI and installed a fresh copy
> of OpenVMS IA64 V8.4-2L3 on the server's internal hard drive.
>
> In the two rx1600 servers, I'm using fibre channel HBAs with the QLogic
> QLA2342 chip. From the EFI shell I've installed the latest EFI driver
> and RISC firmware I could find:
>
> <https://support.hpe.com/connect/s/softwaredetails?language=en_US&softwa
> reId=ux_36358_2>
>
> The card appears to be working properly from OpenVMS:
>
> $ show dev /full fga0
>
> Device FGA0:, device type QLogic ISP23xx FibreChannel, is online, shareable,
> error logging is enabled.
>
> Error count 0 Operations completed 12
> Owner process "" Owner UIC [SYSTEM]
> Owner process ID 00000000 Dev Prot S:RWPL,O:RWPL,G,W
> Reference count 0 Default buffer size 0
> Current preferred CPU Id 1 Fastpath 1
> Current Interrupt CPU Id 1
> FC Port Name 2100-00E0-8B09-B261 FC Node Name 2100-00E0-8B09-B261
>
> I've been able to set up the target LUNs in FreeBSD with the "device-id"
> option, which seems to satisfy OpenVMS's need for the UDID value; e.g.
> if I set the device-id to 0x00000001, the device shows up as $1$DGA1 in
> VMS, if I set it so 0x00000002, it shows up as $1$DGA2, etc.
>
> The two LUNs appears as follows:
>
> $ show dev dga
>
> Device Device Error Volume Free Trans Mnt
> Name Status Count Label Blocks Count Cnt
> $1$DGA1: (IVMS1) Offline 1
> $1$DGA2: (IVMS1) Offline 1
>
> Or one of them in more detail:
>
> $ show dev /full dga1
>
> Disk $1$DGA1: (IVMS1), device type unknown, is offline, file-oriented device,
> shareable, available to cluster, error logging is enabled.
>
> Error count 1 Operations completed 0
> Owner process "" Owner UIC [SYSTEM]
> Owner process ID 00000000 Dev Prot S:RWPL,O:RWPL,G:R,W
> Reference count 0 Default buffer size 512
> WWID 01000010:6008-05F3-0012-00F0-0000-0000-0375-0000
> Allocation class 1
>
> So VMS knows the LUNs are there, but something still seems to be missing
> to make VMS happy, and the devices just stay "Offline" with 1 in the
> Error Count.
>
> For lack of knowing what else to do, I ended up "faking" MSA1000
> volumes, in case VMS was sensitive to particular devices. But I don't
> think VMS really cares what the devices identify themselves as.
>
> In any case, SYS$ETC:FIBRE_SCAN doesn't reveal any errors or problems.
> The target and LUNs show up as I'd expect:
>
> $ run sys$etc:fibre_scan
> [...]
> Probing Target 1 ==========================================================
>
> Port WWID: 5001-4380-28CC-9A38
> Node WWID: 5001-4380-28CC-9A38
>
> Target = 1. LUN = 0.
> ----------------------
> Devname: $1$DGA1:
> Vendor ID: COMPAQ
> Product ID: MSA1000 VOLUME
> Devtype: 0 (Disk)
> Rev Level: 4.32
> WWID: 01000010:6008-05F3-0012-00F0-0000-0000-0375-0000
>
> Reported LUN count = 2. at target 1.
>
> Target = 1. LUN = 1.
> ----------------------
> Devname: $1$DGA2:
> Vendor ID: COMPAQ
> Product ID: MSA1000 VOLUME
> Devtype: 0 (Disk)
> Rev Level: 4.32
> WWID: 01000010:6008-05F3-0012-00F0-0000-0000-0375-0001
> [...]
>
> Here's an example of how I have one of the LUNs configure on the FreeBSD
> side. Mostly made-up/faked values for the serial, vendor, product,
> revision, just based on some working system in the wild in case there is
> anything magical about needing to be a "COMPAQ" vendor or something. The
> ident_info seems to be the magic that maps to UDID:
>
> lun 0 {
> backend block
> device-id "600805f3001200f00000000003750000"
> serial "MGKSERIAL0000"
> option vendor "COMPAQ"
> option product "MSA1000 VOLUME"
> option revision "4.32"
> option scsiname "0001"
> option ident_info 0x00000001
> option naa 600805f3001200f00000000003750000
> path /dev/zvol/zroot/fc/vms00
> }
>
> Obviously this isn't a supported configuration by any means, but I'm
> wondering if anyone has gone down this path before, or has any hints as
> to determine what the error is, or if there's anything in the above
> setup that looks like it might cause a problem?
>
> Thanks,
> Matthew
>

Perhaps the first thing to verify is that the drives under vms can
be mounted, then verify that data can be written to and read back.
Then perhaps export the drives using nfs and verify that they
can be mounted, written to and read back at the FreeBSD end.
That would prove that the hardware and os interface is working,
then go on from there...

Chris

On 4/24/2022 2:18 AM, Matthew R. Wilson wrote:
> This could be a long shot, but I'm hoping to experiment with OpenVMS
> clustering using a shared system disk over fibre channel.
>
> My two VMS systems are Integrity rx1600s. I'm trying to use a system
> running FreeBSD as the target. After much experimentation and
> troubleshooting, I've gotten pretty far, but the volumes are still stuck
> "offline" in OpenVMS.

I'm inferring that there is no fibre switch between VMS and the "storage array".

VMS does not support FC-AL (arbitrated loop).

That's probably among the issues.

--
-- Rob

On 2022-04-24 12:47:21 +0000, Robert A. Brooks said:

> On 4/24/2022 2:18 AM, Matthew R. Wilson wrote:
>> This could be a long shot, but I'm hoping to experiment with OpenVMS
>> clustering using a shared system disk over fibre channel.
>>
>> My two VMS systems are Integrity rx1600s. I'm trying to use a system
>> running FreeBSD as the target. After much experimentation and
>> troubleshooting, I've gotten pretty far, but the volumes are still
>> stuck "offline" in OpenVMS.
>
> I'm inferring that there is no fibre switch between VMS and the
> "storage array".
>
> VMS does not support FC-AL (arbitrated loop).
>
> That's probably among the issues.

Doc here tends to be... messy.

I'd start with a (good) summary of the basics of connecting Fibre
Channel to OpenVMS posted in a thread here in the comp.os.vms
newsgroup:
https://groups.google.com/g/comp.os.vms/c/m-F8ucLqMBc/m/9IWuSvaIZq4J

HP/HPE had a document named the HPE SAN Design Guide, older versions
were hp StorageWorks SAN Design, and in somewhat less antediluvian
times and as OpenVMS information in that HPE SAN document and in SPOCK
disappeared there was an informal OpenVMS-focused version of that SAN
User's Guide briefly around, too. VSI doesn't have much published doc
in this storage-integration area past the two clustering manuals and
some HBA-related docs, AFAIK. For the HPE SAN doc: STNW-SDRG-ED102
https://www.hpe.com/psnow/doc/c00403562

If you want shared storage on a couple of those low-profile
rack-n-stack-n-screech leaf-blowers, shared multi-host SCSI with
TCQ-capable controllers and an MSA30-MI multi-initiator shelf can be
another option. If you can source that SCSI hardware.

As might well be clear already, any two-host cluster is necessarily
primary-secondary, or manual failover, without multi-path shared
storage configured.

OpenVMS shared storage support is largely limited to DAS and FC SAN for
the foreseeable future, and I wouldn't expect SMB client support
(TrueNAS, Synology, etc) or ilk added, nor iSCSI TOE, nor for
newer/weirder stuff such as eSSD / NVMe-oF / computational storage,
etc.; not until well past the completion of the port.
https://www.snia.org/educational-library/ethernet-attached-ssds—brilliant-idea-or-storage-silliness-2020

--
Pure Personal Opinion | HoffmanLabs LLC

On 2022-04-24, Robert A. Brooks <FIRST.LAST@vmssoftware.com> wrote:
> On 4/24/2022 2:18 AM, Matthew R. Wilson wrote:
>> This could be a long shot, but I'm hoping to experiment with OpenVMS
>> clustering using a shared system disk over fibre channel.
>>
>> My two VMS systems are Integrity rx1600s. I'm trying to use a system
>> running FreeBSD as the target. After much experimentation and
>> troubleshooting, I've gotten pretty far, but the volumes are still
>> stuck "offline" in OpenVMS.
>
> I'm inferring that there is no fibre switch between VMS and the
> "storage array".
>
> VMS does not support FC-AL (arbitrated loop).

There is a fibre switch (QLogic SANbox 5802V).

It feels like it *should* be working because the OpenVMS system does see
the LUNs and even assigns them device names (DGA1 and DGA2 corresponding
to UDID 1 and UDID 2 that I assign on the target side), they're just
frustratingly stuck "offline" with an error.

I've turned debug logging up pretty high on the FreeBSD side, and I'm
not seeing anything that looks like a SCSI command error or anything
like that. So I wonder if there's just some magic bit in some
inquire/sense data that needs to be set to make OpenVMS happy. Even if
there's some SCSI command that FreeBSD target support doesn't implement,
it'd be nice to know what command it is so that I could try to add it to
FreeBSD.

Looking at various historical documentation from various SAN vendors, I
see many products had things like an "OpenVMS host mode". This would let
you set UDID, but I suspect they also know of some other values you need
to return in response to certain SCSI/FC commands to satisfy VMS. At
some point someone at SAN vendors knew what the magic was...but I can't
find it documented anywhere.

Is there any way to know what the error is on the VMS side? If I run
ANALYZE/ERROR/ELV and then have it TRANSLATE to an output file, I don't
see anything obvious. I just booted the server up, and here's
everything:

<https://mattwilson.org/filedrop/20220425-vms-error-log.txt>

There are no entries with class DEVICE_ERRORS, but I do see a couple
TIMEOUTS and ATTENTIONS. SHOW ERROR currently reports:

Device Error Count
IVMS1$DQA1: 1
$1$DGA1: (IVMS1 FGA) 2
$1$DGA2: (IVMS1 FGA) 2

In the error log there are 4 "ATTENTIONS" and 1 "TIMEOUTS", so perhaps
the timeout is DQA1 and the 4 attentions correspond with the four DGA
errors?

Is there a way to know what the attentions mean? "Device type 54, OS
flags 0x0001" doesn't really pin down the potential problem!

Thanks,
Matthew

On Monday, April 25, 2022 at 11:38:16 PM UTC+1, Matthew R. Wilson wrote:
> On 2022-04-24, Robert A. Brooks <FIRST...@vmssoftware.com> wrote:
> > On 4/24/2022 2:18 AM, Matthew R. Wilson wrote:
> >> This could be a long shot, but I'm hoping to experiment with OpenVMS
> >> clustering using a shared system disk over fibre channel.
> >>
> >> My two VMS systems are Integrity rx1600s. I'm trying to use a system
> >> running FreeBSD as the target. After much experimentation and
> >> troubleshooting, I've gotten pretty far, but the volumes are still
> >> stuck "offline" in OpenVMS.
> >
> > I'm inferring that there is no fibre switch between VMS and the
> > "storage array".
> >
> > VMS does not support FC-AL (arbitrated loop).
> There is a fibre switch (QLogic SANbox 5802V).
>
> It feels like it *should* be working because the OpenVMS system does see
> the LUNs and even assigns them device names (DGA1 and DGA2 corresponding
> to UDID 1 and UDID 2 that I assign on the target side), they're just
> frustratingly stuck "offline" with an error.
>
> I've turned debug logging up pretty high on the FreeBSD side, and I'm
> not seeing anything that looks like a SCSI command error or anything
> like that. So I wonder if there's just some magic bit in some
> inquire/sense data that needs to be set to make OpenVMS happy. Even if
> there's some SCSI command that FreeBSD target support doesn't implement,
> it'd be nice to know what command it is so that I could try to add it to
> FreeBSD.
>
> Looking at various historical documentation from various SAN vendors, I
> see many products had things like an "OpenVMS host mode". This would let
> you set UDID, but I suspect they also know of some other values you need
> to return in response to certain SCSI/FC commands to satisfy VMS. At
> some point someone at SAN vendors knew what the magic was...but I can't
> find it documented anywhere.
>
> Is there any way to know what the error is on the VMS side? If I run
> ANALYZE/ERROR/ELV and then have it TRANSLATE to an output file, I don't
> see anything obvious. I just booted the server up, and here's
> everything:
>
> <https://mattwilson.org/filedrop/20220425-vms-error-log.txt>
>
> There are no entries with class DEVICE_ERRORS, but I do see a couple
> TIMEOUTS and ATTENTIONS. SHOW ERROR currently reports:
>
> Device Error Count
> IVMS1$DQA1: 1
> $1$DGA1: (IVMS1 FGA) 2
> $1$DGA2: (IVMS1 FGA) 2
>
> In the error log there are 4 "ATTENTIONS" and 1 "TIMEOUTS", so perhaps
> the timeout is DQA1 and the 4 attentions correspond with the four DGA
> errors?
>
> Is there a way to know what the attentions mean? "Device type 54, OS
> flags 0x0001" doesn't really pin down the potential problem!
>
> Thanks,
> Matthew
the DKLOG or FC SDA extensions on VMS may provide more clues.

You may also have a zoning visibility problem or a host behavior definition problem.

Make sure that both the FC switch and the FreeBSD UDID source allows read/write access from the WWIDs of the Integrity systems, and that they are all in the same zone (or no zone is set).

I've never tried to use a non-Enterprise SAN Array (I'm using an EMC VNX5500 now and have used HP MSAs before) from OpenVMS, but I know that some SAN Arrays (specifically Infortrend) will not connect, due to the fact that they don't support the UDID correctly. I do know that OpenVMS requires specific SCSI-3 commands to be supported by the SAN Array, in addition to the UDID.. For both the EMC VNX5500 and the MSA units, you have to tell the SAN Array that the OpenVMS host WWIDs are specifically OpenVMS or TRU64 ("profile"), which enables certain behavior patterns, or else the systems won't connect properly, as the LUNs assume the (non-OpenVMS-compliant) Windows/VMware/Linux behavior by default.

I've used the QLogic SANBox 5802V to connect VMware and Windows server systems to SAN Arrays, but have never tried to connect an OpenVMS system through a SANbox. I still have a pair of SANboxes, so I might give it a shot in the next week or so.

David

Hi David,

Thanks for your thoughts.

> You may also have a zoning visibility problem or a host behavior
> definition problem.
>
> Make sure that both the FC switch and the FreeBSD UDID source allows
> read/write access from the WWIDs of the Integrity systems, and that
> they are all in the same zone (or no zone is set).

Doesn't look like a visibility problem. OpenVMS sees the target and LUNs
just fine; it creates the DGAxx devices that correspond to the LUNs with
the correct UDID, and SYS$ETC:FIBRE_SCAN reports everything with the
correct addresses.

> I know that some SAN Arrays (specifically Infortrend) will not
> connect, due to the fact that they don't support the UDID correctly.

Yeah, the first problem I had was that the LUNs weren't showing up as
DGAxx devices at all in OpenVMS. That's when I learned about UDID and
figured out how to set it from the FreeBSD target side, and the devices
magically started showing up in OpenVMS... albeit stuck offline.

> I do know that OpenVMS requires specific SCSI-3 commands to be
> supported by the SAN Array, in addition to the UDID. For both the EMC
> VNX5500 and the MSA units, you have to tell the SAN Array that the
> OpenVMS host WWIDs are specifically OpenVMS or TRU64 ("profile"),
> which enables certain behavior patterns, or else the systems won't
> connect properly, as the LUNs assume the (non-OpenVMS-compliant)
> Windows/VMware/Linux behavior by default.

I think that's where the problem probably is: some SCSI command that
OpenVMS isn't liking FreeBSD's response to. I'm trying to track down
what it might be. I have seen the documentation in several SAN products
that they have the "OpenVMS profile/host mode" that you refer to. But
I can't find any documentation on what the SANs do differently when set
in that mode.

My guess is there's some SCSI INQUIRY message or something that needs
certain values in the response to make VMS happy. I just can't find any
documentation about what the specific protocol requirements are...

I just figured out how to turn on debuggin in FreeBSD's SCSI target
driver, so I think I'll be able to see the individual SCSI commands
instead of just the packets from the fibrce channel driver that I was
able to enable debugging on.

I'm probably just going to hit a dead end with all of this... but you
never know. I can afford to burn some more time on it for fun.

Thanks,
Matthew

On 4/27/2022 10:49 PM, Matthew R. Wilson wrote:

> I think that's where the problem probably is: some SCSI command that
> OpenVMS isn't liking FreeBSD's response to. I'm trying to track down
> what it might be. I have seen the documentation in several SAN products

$ scsi_info :== sys$etc:scsi_info
$ scsi_info $1$dga1:

--
-- Rob

On 2022-04-28, Robert A. Brooks <FIRST.LAST@vmssoftware.com> wrote:
> On 4/27/2022 10:49 PM, Matthew R. Wilson wrote:
>
>> I think that's where the problem probably is: some SCSI command that
>> OpenVMS isn't liking FreeBSD's response to. I'm trying to track down
>> what it might be. I have seen the documentation in several SAN products
>
> $ scsi_info :== sys$etc:scsi_info
> $ scsi_info $1$dga1:

Ah... that could help! Perhaps a useful clue:

$ scsi_info $1$DGA2:
$!
$! SCSI_INFO X-5
$!
$! Copyright (c) 2019 by VMS Software, Bolton Mass.
$! All Rights Reserved. Unpublished rights reserved under the copyright
$! laws of the United States.
$!
$! Issuing INQUIRY QIOW
$!
$! QIO status of 132 causing program exit
$!
%SYSTEM-F-DEVOFFLINE, device is not in configuration or not available

Is that SCSI_INFO telling me the device is offline because of a response
it doesn't like to INQUIRY QIOW, or is it SCSI_INFO telling me that it
refuses to run because VMS is telling it the device it offline?

I have the SCSI commands and responses in a debug log on the FreeBSD
side now. I have some SCSI books and specs open and am decoding them...
but the general INQUIRY messages and responses during VMS startup are...

INQUIRY. CDB: 12 00 00 00 ff 00 Tag: 0x118b60/1, Prio: 0
0x118b60:0000: 00 00 07 12 5b 18 10 02 43 4f 4d 50 41 51 20 20
0x118b60:0010: 4d 53 41 31 30 30 30 20 56 4f 4c 55 4d 45 20 20
0x118b60:0020: 34 2e 33 32 00 00 00 00 00 00 00 00 00 00 00 00
0x118b60:0030: 00 00 00 00 00 00 00 00 00 00 00 c0 05 c0 09 17
0x118b60:0040: 06 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
0x118b60:0050: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

INQUIRY. CDB: 12 01 00 00 50 00 Tag: 0x118bf0/1, Prio: 0
0x118bf0:0000: 00 00 00 0b 00 80 83 86 87 88 8f 92 b0 b1 b2 00
0x118bf0:0010: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
0x118bf0:0020: 00 00 00 00 00 00 00 00 00 00 00 00

INQUIRY. CDB: 12 01 83 00 ff 00 Tag: 0x118c80/1, Prio: 0
0x118c80:0000: 00 83 00 58 02 81 00 18 43 4f 4d 50 41 51 20 20
0x118c80:0010: 35 30 30 30 63 35 30 30 31 64 35 62 61 33 30 63
0x118c80:0020: 01 83 00 10 60 08 05 f3 00 12 00 f0 00 00 00 00
0x118c80:0030: 03 75 00 01 01 93 00 08 50 01 43 80 28 cc 9a 38
0x118c80:0040: 01 94 00 04 00 00 00 03 01 95 00 04 00 00 00 01
0x118c80:0050: 01 a3 00 08 50 01 43 80 28 cc 9a ff

There's also this during VMS startup... not sure if this is an _actual_
error or if the "power on occurred" unit attention "error" is an
expected part of the process:

MAINTENANCE (IN). CDB: a3 05 00 00 00 00 00 00 00 0c 00 00 Tag: 0x118c20/1, Prio: 0
CTL Status: SCSI Error
SCSI Status: Check Condition
SCSI sense: UNIT ATTENTION asc:29,1 (Power on occurred)
MAINTENANCE (IN). CDB: a3 05 00 00 00 00 00 00 00 0c 00 00 Tag: 0x118c50/1, Prio: 0
0x118c50:0000: 00 00 00 04 00 00 00 02 00 00 00 00

Then every 30 seconds:

INQUIRY. CDB: 12 00 00 00 80 00 Tag: 0x118da0/0, Prio: 0
0x118da0:0000: 00 00 07 12 5b 18 10 02 43 4f 4d 50 41 51 20 20
0x118da0:0010: 4d 53 41 31 30 30 30 20 56 4f 4c 55 4d 45 20 20
0x118da0:0020: 34 2e 33 32 00 00 00 00 00 00 00 00 00 00 00 00
0x118da0:0030: 00 00 00 00 00 00 00 00 00 00 00 c0 05 c0 09 17
0x118da0:0040: 06 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
0x118da0:0050: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

Will have to see if any of this makes sense in the context of the
SCSI_INFO command saying "INQUIRY QIOW" and "QIO status of 132 causing
program exit", or if that's just an internal VMS thing. No hex 0x84 (132
decimal) is in any of the command responses above.

Thanks,
Matthew

Matthew,

the value 132 is the system service status code:

VSIAXP $ exit 132
%SYSTEM-F-DEVOFFLINE, device is not in configuration or not available

Here is the SCSI_INFO data from an emulated DGA device on a CHARON-AXP emulator:

VSIAXP $ scsi_info $1$dga0
$!
$! SCSI_INFO V3
$!
$! Copyright (c) 1995 by DIGITAL Equipment Corporation, Maynard, Mass.
$! All Rights Reserved. Unpublished rights reserved under the copyright
$! laws of the United States.
$!
$! Issuing INQUIRY QIOW
$!
$! SCSI Inquiry Data (255 bytes) :
$!
$! 000: 00 00 02 02 1F 00 00 53 56 69 72 74 75 61 6C 20
$! 010: 48 53 56 33 30 30 20 20 20 20 20 20 20 20 20 20
$! 020: 30 32 30 30 00 00 00 00 00 00 00 00 00 00 00 00
$! 030: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
$! 040: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
$! 050: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
$! 060: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
$! 070: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
$! 080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
$! 090: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
$! 0A0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
$! 0B0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
$! 0C0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
$! 0D0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
$! 0E0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
$! 0F0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
$!
$! Peripheral Device Type : Direct Access
$!
$! Peripheral Device Qualifier :
$!
$! Peripheral device type supported & connected to target
$!
$! Vendor Identification : Virtual
$!
$! Product Identification: HSV300
$!
$! Product Revision Level: 0200
$!
$! ANSI Information:
$!
$! Complies to SCSI-2
$!
$! ISO Information:
$!
$! 0 - does not claim ISO SCSI (ISO IS 9316) compliance
$!
$! ECMA Information:
$!
$! 0 - does not claim ECMA SCSI (ECMA-111) compliance
$!
$! Removable Media: No
$!
$! AEN Capability: No
$!
$! Command Queuing: Yes
$!
$! 16-Bit Wide Bus Data Transfers: No
$!
$! 32-Bit Wide Bus Data Transfers: Yes
$!
$! Linked Commands: No
$!
$! Soft Reset Alternative: Yes
$!
$! Relative Addressing: No
$!
$! Synchronous Data Transfers: Yes
$!
$! Issuing Test Unit Ready command
$!
$! ========================== Read-Write Error Recovery Page ==================
$!
$! Issuing 6-byte MODE SENSE QIOW to get current values for page 01h
$!
$! SCSI 6-Byte Mode Sense command returned 24 bytes of data:
$!
$! 000: 17 00 00 08 00 00 00 00 00 00 02 00 01 0A 00 00
$! 010: 00 00 00 00 00 00 00 00
$!
$! Mode Sense Data Length ...... 23
$! Medium Type ................. 00h
$! Device-Specific Parameter ... 00h
$! Block Descriptor Length ..... 8
$! Block Descriptor Data ....... 00 00 00 00 00 00 02 00
$!
$! Page Code ................. 01h
$! Page Name ................. Read-Write Error Recovery
$! Saveable .................. No
$! Size ...................... 10
$! Hex Data .................. 00 00 00 00 00 00 00 00
$! 00 00
$!
$! Issuing 6-byte MODE SENSE QIOW to get changeable values for page 01h
$!
$! SCSI 6-Byte Mode Sense command returned 24 bytes of data:
$!
$! 000: 17 00 00 08 00 00 00 00 00 00 02 00 01 0A FF FF
$! 010: FF FF FF 00 FF 00 FF FF
$!
$! Mode Sense Data Length ...... 23
$! Medium Type ................. 00h
$! Device-Specific Parameter ... 00h
$! Block Descriptor Length ..... 8
$! Block Descriptor Data ....... 00 00 00 00 00 00 02 00
$!
$! Page Code ................. 01h
$! Page Name ................. Read-Write Error Recovery
$! Saveable .................. No
$! Size ...................... 10
$! Hex Data .................. FF FF FF FF FF 00 FF 00
$! FF FF
$!
$! Issuing 10-byte MODE SENSE QIOW to get current values for page 01h
$!
$! SCSI 10-Byte Mode Sense command returned 28 bytes of data:
$!
$! 000: 00 1A 00 00 00 00 00 08 00 00 00 00 00 00 02 00
$! 010: 01 0A 00 00 00 00 00 00 00 00 00 00
$!
$! Mode Sense Data Length ...... 26
$! Medium Type ................. 00h
$! Device-Specific Parameter ... 00h
$! Block Descriptor Length ..... 8
$! Block Descriptor Data ....... 00 00 00 00 00 00 02 00
$!
$! Page Code ................. 01h
$! Page Name ................. Read-Write Error Recovery
$! Saveable .................. No
$! Size ...................... 10
$! Hex Data .................. 00 00 00 00 00 00 00 00
$! 00 00
$!
$! Issuing 10-byte MODE SENSE QIOW to get changeable values for page 01h
$!
$! SCSI 10-Byte Mode Sense command returned 28 bytes of data:
$!
$! 000: 00 1A 00 00 00 00 00 08 00 00 00 00 00 00 02 00
$! 010: 01 0A FF FF FF FF FF 00 FF 00 FF FF
$!
$! Mode Sense Data Length ...... 26
$! Medium Type ................. 00h
$! Device-Specific Parameter ... 00h
$! Block Descriptor Length ..... 8
$! Block Descriptor Data ....... 00 00 00 00 00 00 02 00
$!
$! Page Code ................. 01h
$! Page Name ................. Read-Write Error Recovery
$! Saveable .................. No
$! Size ...................... 10
$! Hex Data .................. FF FF FF FF FF 00 FF 00
$! FF FF
$!
$! ============================ Disconnect-Reconnect Page =====================
$!
$! Issuing 6-byte MODE SENSE QIOW to get current values for page 02h
$!
$! SCSI 6-Byte Mode Sense command returned 28 bytes of data:
$!
$! 000: 1B 00 00 08 00 00 00 00 00 00 02 00 02 0E 00 00
$! 010: 00 00 00 00 00 00 00 00 00 00 00 00
$!
$! Mode Sense Data Length ...... 27
$! Medium Type ................. 00h
$! Device-Specific Parameter ... 00h
$! Block Descriptor Length ..... 8
$! Block Descriptor Data ....... 00 00 00 00 00 00 02 00
$!
$! Page Code ................. 02h
$! Page Name ................. Disconnect-Reconnect
$! Saveable .................. No
$! Size ...................... 14
$! Hex Data .................. 00 00 00 00 00 00 00 00
$! 00 00 00 00 00 00
$!
$! Issuing 6-byte MODE SENSE QIOW to get changeable values for page 02h
$!
$! SCSI 6-Byte Mode Sense command returned 28 bytes of data:
$!
$! 000: 1B 00 00 08 00 00 00 00 00 00 02 00 02 0E 00 00
$! 010: 00 00 00 00 00 00 00 00 00 00 00 00
$!
$! Mode Sense Data Length ...... 27
$! Medium Type ................. 00h
$! Device-Specific Parameter ... 00h
$! Block Descriptor Length ..... 8
$! Block Descriptor Data ....... 00 00 00 00 00 00 02 00
$!
$! Page Code ................. 02h
$! Page Name ................. Disconnect-Reconnect
$! Saveable .................. No
$! Size ...................... 14
$! Hex Data .................. 00 00 00 00 00 00 00 00
$! 00 00 00 00 00 00
$!
$! Issuing 10-byte MODE SENSE QIOW to get current values for page 02h
$!
$! SCSI 10-Byte Mode Sense command returned 32 bytes of data:
$!
$! 000: 00 1E 00 00 00 00 00 08 00 00 00 00 00 00 02 00
$! 010: 02 0E 00 00 00 00 00 00 00 00 00 00 00 00 00 00
$!
$! Mode Sense Data Length ...... 30
$! Medium Type ................. 00h
$! Device-Specific Parameter ... 00h
$! Block Descriptor Length ..... 8
$! Block Descriptor Data ....... 00 00 00 00 00 00 02 00
$!
$! Page Code ................. 02h
$! Page Name ................. Disconnect-Reconnect
$! Saveable .................. No
$! Size ...................... 14
$! Hex Data .................. 00 00 00 00 00 00 00 00
$! 00 00 00 00 00 00
$!
$! Issuing 10-byte MODE SENSE QIOW to get changeable values for page 02h
$!
$! SCSI 10-Byte Mode Sense command returned 32 bytes of data:
$!
$! 000: 00 1E 00 00 00 00 00 08 00 00 00 00 00 00 02 00
$! 010: 02 0E 00 00 00 00 00 00 00 00 00 00 00 00 00 00
$!
$! Mode Sense Data Length ...... 30
$! Medium Type ................. 00h
$! Device-Specific Parameter ... 00h
$! Block Descriptor Length ..... 8
$! Block Descriptor Data ....... 00 00 00 00 00 00 02 00
$!
$! Page Code ................. 02h
$! Page Name ................. Disconnect-Reconnect
$! Saveable .................. No
$! Size ...................... 14
$! Hex Data .................. 00 00 00 00 00 00 00 00
$! 00 00 00 00 00 00
$!
$! ================================ Format Device Page ========================
$!
$! Issuing 6-byte MODE SENSE QIOW to get current values for page 03h
$!
$! SCSI 6-Byte Mode Sense command returned 36 bytes of data:
$!
$! 000: 23 00 00 08 00 00 00 00 00 00 02 00 03 16 00 00
$! 010: 00 00 00 00 00 00 00 3F 02 00 00 00 00 00 00 00
$! 020: 00 00 00 00
$!
$! Mode Sense Data Length ...... 35
$! Medium Type ................. 00h
$! Device-Specific Parameter ... 00h
$! Block Descriptor Length ..... 8
$! Block Descriptor Data ....... 00 00 00 00 00 00 02 00
$!
$! Page Code ................. 03h
$! Page Name ................. Format Device
$! Saveable .................. No
$! Size ...................... 22
$! Hex Data .................. 00 00 00 00 00 00 00 00
$! 00 3F 02 00 00 00 00 00 00 00 00 00 00 00
$!
$! Issuing 6-byte MODE SENSE QIOW to get changeable values for page 03h
$!
$! SCSI 6-Byte Mode Sense command returned 36 bytes of data:
$!
$! 000: 23 00 00 08 00 00 00 00 00 00 02 00 03 16 00 00
$! 010: 00 00 00 00 00 00 00 3F 02 00 00 00 00 00 00 00
$! 020: 00 00 00 00
$!
$! Mode Sense Data Length ...... 35
$! Medium Type ................. 00h
$! Device-Specific Parameter ... 00h
$! Block Descriptor Length ..... 8
$! Block Descriptor Data ....... 00 00 00 00 00 00 02 00
$!
$! Page Code ................. 03h
$! Page Name ................. Format Device
$! Saveable .................. No
$! Size ...................... 22
$! Hex Data .................. 00 00 00 00 00 00 00 00
$! 00 3F 02 00 00 00 00 00 00 00 00 00 00 00
$!
$! Issuing 10-byte MODE SENSE QIOW to get current values for page 03h
$!
$! SCSI 10-Byte Mode Sense command returned 40 bytes of data:
$!
$! 000: 00 26 00 00 00 00 00 08 00 00 00 00 00 00 02 00
$! 010: 03 16 00 00 00 00 00 00 00 00 00 3F 02 00 00 00
$! 020: 00 00 00 00 00 00 00 00
$!
$! Mode Sense Data Length ...... 38
$! Medium Type ................. 00h
$! Device-Specific Parameter ... 00h
$! Block Descriptor Length ..... 8
$! Block Descriptor Data ....... 00 00 00 00 00 00 02 00
$!
$! Page Code ................. 03h
$! Page Name ................. Format Device
$! Saveable .................. No
$! Size ...................... 22
$! Hex Data .................. 00 00 00 00 00 00 00 00
$! 00 3F 02 00 00 00 00 00 00 00 00 00 00 00
$!
$! Issuing 10-byte MODE SENSE QIOW to get changeable values for page 03h
$!
$! SCSI 10-Byte Mode Sense command returned 40 bytes of data:
$!
$! 000: 00 26 00 00 00 00 00 08 00 00 00 00 00 00 02 00
$! 010: 03 16 00 00 00 00 00 00 00 00 00 3F 02 00 00 00
$! 020: 00 00 00 00 00 00 00 00
$!
$! Mode Sense Data Length ...... 38
$! Medium Type ................. 00h
$! Device-Specific Parameter ... 00h
$! Block Descriptor Length ..... 8
$! Block Descriptor Data ....... 00 00 00 00 00 00 02 00
$!
$! Page Code ................. 03h
$! Page Name ................. Format Device
$! Saveable .................. No
$! Size ...................... 22
$! Hex Data .................. 00 00 00 00 00 00 00 00
$! 00 3F 02 00 00 00 00 00 00 00 00 00 00 00
$!
$! ============================= Rigid Disk Geometry Page =====================
$!
$! Issuing 6-byte MODE SENSE QIOW to get current values for page 04h
$!
$! SCSI 6-Byte Mode Sense command returned 36 bytes of data:
$!
$! 000: 23 00 00 08 00 00 00 00 00 00 02 00 04 16 00 00
$! 010: 1A 3F 00 00 00 00 00 00 00 00 00 00 00 00 00 00
$! 020: 15 18 00 00
$!
$! Mode Sense Data Length ...... 35
$! Medium Type ................. 00h
$! Device-Specific Parameter ... 00h
$! Block Descriptor Length ..... 8
$! Block Descriptor Data ....... 00 00 00 00 00 00 02 00
$!
$! Page Code ................. 04h
$! Page Name ................. Rigid Disk Geometry
$! Saveable .................. No
$! Size ...................... 22
$! Hex Data .................. 00 00 1A 3F 00 00 00 00
$! 00 00 00 00 00 00 00 00 00 00 15 18 00 00
$!
$! Issuing 6-byte MODE SENSE QIOW to get changeable values for page 04h
$!
$! SCSI 6-Byte Mode Sense command returned 36 bytes of data:
$!
$! 000: 23 00 00 08 00 00 00 00 00 00 02 00 04 16 00 00
$! 010: 1A 3F 00 00 00 00 00 00 00 00 00 00 00 00 00 00
$! 020: 00 00 00 00
$!
$! Mode Sense Data Length ...... 35
$! Medium Type ................. 00h
$! Device-Specific Parameter ... 00h
$! Block Descriptor Length ..... 8
$! Block Descriptor Data ....... 00 00 00 00 00 00 02 00
$!
$! Page Code ................. 04h
$! Page Name ................. Rigid Disk Geometry
$! Saveable .................. No
$! Size ...................... 22
$! Hex Data .................. 00 00 1A 3F 00 00 00 00
$! 00 00 00 00 00 00 00 00 00 00 00 00 00 00
$!
$! Issuing 10-byte MODE SENSE QIOW to get current values for page 04h
$!
$! SCSI 10-Byte Mode Sense command returned 40 bytes of data:
$!
$! 000: 00 26 00 00 00 00 00 08 00 00 00 00 00 00 02 00
$! 010: 04 16 00 00 1A 3F 00 00 00 00 00 00 00 00 00 00
$! 020: 00 00 00 00 15 18 00 00
$!
$! Mode Sense Data Length ...... 38
$! Medium Type ................. 00h
$! Device-Specific Parameter ... 00h
$! Block Descriptor Length ..... 8
$! Block Descriptor Data ....... 00 00 00 00 00 00 02 00
$!
$! Page Code ................. 04h
$! Page Name ................. Rigid Disk Geometry
$! Saveable .................. No
$! Size ...................... 22
$! Hex Data .................. 00 00 1A 3F 00 00 00 00
$! 00 00 00 00 00 00 00 00 00 00 15 18 00 00
$!
$! Issuing 10-byte MODE SENSE QIOW to get changeable values for page 04h
$!
$! SCSI 10-Byte Mode Sense command returned 40 bytes of data:
$!
$! 000: 00 26 00 00 00 00 00 08 00 00 00 00 00 00 02 00
$! 010: 04 16 00 00 1A 3F 00 00 00 00 00 00 00 00 00 00
$! 020: 00 00 00 00 00 00 00 00
$!
$! Mode Sense Data Length ...... 38
$! Medium Type ................. 00h
$! Device-Specific Parameter ... 00h
$! Block Descriptor Length ..... 8
$! Block Descriptor Data ....... 00 00 00 00 00 00 02 00
$!
$! Page Code ................. 04h
$! Page Name ................. Rigid Disk Geometry
$! Saveable .................. No
$! Size ...................... 22
$! Hex Data .................. 00 00 1A 3F 00 00 00 00
$! 00 00 00 00 00 00 00 00 00 00 00 00 00 00
$!
$! ================================ Flexible Disk Page ========================
$!
$! Issuing 6-byte MODE SENSE QIOW to get current values for page 05h
$!
$! SCSI 6-Byte Mode Sense command returned 44 bytes of data:
$!
$! 000: 2B 00 00 08 00 00 00 00 00 00 02 00 05 1E 00 FA
$! 010: 02 0F 02 00 00 50 00 00 00 00 00 00 00 00 00 00
$! 020: 00 00 00 00 00 00 00 00 00 00 00 00
$!
$! Mode Sense Data Length ...... 43
$! Medium Type ................. 00h
$! Device-Specific Parameter ... 00h
$! Block Descriptor Length ..... 8
$! Block Descriptor Data ....... 00 00 00 00 00 00 02 00
$!
$! Page Code ................. 05h
$! Page Name ................. Flexible Disk
$! Saveable .................. No
$! Size ...................... 30
$! Hex Data .................. 00 FA 02 0F 02 00 00 50
$! 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00
$! 00 00 00 00 00 00
$!
$! Issuing 6-byte MODE SENSE QIOW to get changeable values for page 05h
$!
$! SCSI 6-Byte Mode Sense command returned 44 bytes of data:
$!
$! 000: 2B 00 00 08 00 00 00 00 00 00 02 00 05 1E 00 00
$! 010: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
$! 020: 00 00 00 00 00 00 00 00 00 00 00 00
$!
$! Mode Sense Data Length ...... 43
$! Medium Type ................. 00h
$! Device-Specific Parameter ... 00h
$! Block Descriptor Length ..... 8
$! Block Descriptor Data ....... 00 00 00 00 00 00 02 00
$!
$! Page Code ................. 05h
$! Page Name ................. Flexible Disk
$! Saveable .................. No
$! Size ...................... 30
$! Hex Data .................. 00 00 00 00 00 00 00 00
$! 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00
$! 00 00 00 00 00 00
$!
$! Issuing 10-byte MODE SENSE QIOW to get current values for page 05h
$!
$! SCSI 10-Byte Mode Sense command returned 48 bytes of data:
$!
$! 000: 00 2E 00 00 00 00 00 08 00 00 00 00 00 00 02 00
$! 010: 05 1E 00 FA 02 0F 02 00 00 50 00 00 00 00 00 00
$! 020: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
$!
$! Mode Sense Data Length ...... 46
$! Medium Type ................. 00h
$! Device-Specific Parameter ... 00h
$! Block Descriptor Length ..... 8
$! Block Descriptor Data ....... 00 00 00 00 00 00 02 00
$!
$! Page Code ................. 05h
$! Page Name ................. Flexible Disk
$! Saveable .................. No
$! Size ...................... 30
$! Hex Data .................. 00 FA 02 0F 02 00 00 50
$! 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00
$! 00 00 00 00 00 00
$!
$! Issuing 10-byte MODE SENSE QIOW to get changeable values for page 05h
$!
$! SCSI 10-Byte Mode Sense command returned 48 bytes of data:
$!
$! 000: 00 2E 00 00 00 00 00 08 00 00 00 00 00 00 02 00
$! 010: 05 1E 00 00 00 00 00 00 00 00 00 00 00 00 00 00
$! 020: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
$!
$! Mode Sense Data Length ...... 46
$! Medium Type ................. 00h
$! Device-Specific Parameter ... 00h
$! Block Descriptor Length ..... 8
$! Block Descriptor Data ....... 00 00 00 00 00 00 02 00
$!
$! Page Code ................. 05h
$! Page Name ................. Flexible Disk
$! Saveable .................. No
$! Size ...................... 30
$! Hex Data .................. 00 00 00 00 00 00 00 00
$! 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00
$! 00 00 00 00 00 00
$!
$! ============================ Verify Error Recovery Page ====================
$!
$! Issuing 6-byte MODE SENSE QIOW to get current values for page 07h
$!
$! SCSI 6-Byte Mode Sense command returned 24 bytes of data:
$!
$! 000: 17 00 00 08 00 00 00 00 00 00 02 00 07 0A 00 00
$! 010: 00 00 00 00 00 00 00 00
$!
$! Mode Sense Data Length ...... 23
$! Medium Type ................. 00h
$! Device-Specific Parameter ... 00h
$! Block Descriptor Length ..... 8
$! Block Descriptor Data ....... 00 00 00 00 00 00 02 00
$!
$! Page Code ................. 07h
$! Page Name ................. Verify Error Recovery
$! Saveable .................. No
$! Size ...................... 10
$! Hex Data .................. 00 00 00 00 00 00 00 00
$! 00 00
$!
$! Issuing 6-byte MODE SENSE QIOW to get changeable values for page 07h
$!
$! SCSI 6-Byte Mode Sense command returned 24 bytes of data:
$!
$! 000: 17 00 00 08 00 00 00 00 00 00 02 00 07 0A 0F FF
$! 010: FF 00 00 00 00 00 FF FF
$!
$! Mode Sense Data Length ...... 23
$! Medium Type ................. 00h
$! Device-Specific Parameter ... 00h
$! Block Descriptor Length ..... 8
$! Block Descriptor Data ....... 00 00 00 00 00 00 02 00
$!
$! Page Code ................. 07h
$! Page Name ................. Verify Error Recovery
$! Saveable .................. No
$! Size ...................... 10
$! Hex Data .................. 0F FF FF 00 00 00 00 00
$! FF FF
$!
$! Issuing 10-byte MODE SENSE QIOW to get current values for page 07h
$!
$! SCSI 10-Byte Mode Sense command returned 28 bytes of data:
$!
$! 000: 00 1A 00 00 00 00 00 08 00 00 00 00 00 00 02 00
$! 010: 07 0A 00 00 00 00 00 00 00 00 00 00
$!
$! Mode Sense Data Length ...... 26
$! Medium Type ................. 00h
$! Device-Specific Parameter ... 00h
$! Block Descriptor Length ..... 8
$! Block Descriptor Data ....... 00 00 00 00 00 00 02 00
$!
$! Page Code ................. 07h
$! Page Name ................. Verify Error Recovery
$! Saveable .................. No
$! Size ...................... 10
$! Hex Data .................. 00 00 00 00 00 00 00 00
$! 00 00
$!
$! Issuing 10-byte MODE SENSE QIOW to get changeable values for page 07h
$!
$! SCSI 10-Byte Mode Sense command returned 28 bytes of data:
$!
$! 000: 00 1A 00 00 00 00 00 08 00 00 00 00 00 00 02 00
$! 010: 07 0A 0F FF FF 00 00 00 00 00 FF FF
$!
$! Mode Sense Data Length ...... 26
$! Medium Type ................. 00h
$! Device-Specific Parameter ... 00h
$! Block Descriptor Length ..... 8
$! Block Descriptor Data ....... 00 00 00 00 00 00 02 00
$!
$! Page Code ................. 07h
$! Page Name ................. Verify Error Recovery
$! Saveable .................. No
$! Size ...................... 10
$! Hex Data .................. 0F FF FF 00 00 00 00 00
$! FF FF
$!
$! =================================== Caching Page ===========================
$!
$! Issuing 6-byte MODE SENSE QIOW to get current values for page 08h
$!
$! SCSI 6-Byte Mode Sense command returned 24 bytes of data:
$!
$! 000: 17 00 00 08 00 00 00 00 00 00 02 00 08 0A 00 00
$! 010: 00 00 00 00 00 00 00 00
$!
$! Mode Sense Data Length ...... 23
$! Medium Type ................. 00h
$! Device-Specific Parameter ... 00h
$! Block Descriptor Length ..... 8
$! Block Descriptor Data ....... 00 00 00 00 00 00 02 00
$!
$! Page Code ................. 08h
$! Page Name ................. Caching
$! Saveable .................. No
$! Size ...................... 10
$! Hex Data .................. 00 00 00 00 00 00 00 00
$! 00 00
$!
$! Issuing 6-byte MODE SENSE QIOW to get changeable values for page 08h
$!
$! SCSI 6-Byte Mode Sense command returned 24 bytes of data:
$!
$! 000: 17 00 00 08 00 00 00 00 00 00 02 00 08 0A 07 FF
$! 010: FF FF FF FF FF FF FF FF
$!
$! Mode Sense Data Length ...... 23
$! Medium Type ................. 00h
$! Device-Specific Parameter ... 00h
$! Block Descriptor Length ..... 8
$! Block Descriptor Data ....... 00 00 00 00 00 00 02 00
$!
$! Page Code ................. 08h
$! Page Name ................. Caching
$! Saveable .................. No
$! Size ...................... 10
$! Hex Data .................. 07 FF FF FF FF FF FF FF
$! FF FF
$!
$! Issuing 10-byte MODE SENSE QIOW to get current values for page 08h
$!
$! SCSI 10-Byte Mode Sense command returned 28 bytes of data:
$!
$! 000: 00 1A 00 00 00 00 00 08 00 00 00 00 00 00 02 00
$! 010: 08 0A 00 00 00 00 00 00 00 00 00 00
$!
$! Mode Sense Data Length ...... 26
$! Medium Type ................. 00h
$! Device-Specific Parameter ... 00h
$! Block Descriptor Length ..... 8
$! Block Descriptor Data ....... 00 00 00 00 00 00 02 00
$!
$! Page Code ................. 08h
$! Page Name ................. Caching
$! Saveable .................. No
$! Size ...................... 10
$! Hex Data .................. 00 00 00 00 00 00 00 00
$! 00 00
$!
$! Issuing 10-byte MODE SENSE QIOW to get changeable values for page 08h
$!
$! SCSI 10-Byte Mode Sense command returned 28 bytes of data:
$!
$! 000: 00 1A 00 00 00 00 00 08 00 00 00 00 00 00 02 00
$! 010: 08 0A 07 FF FF FF FF FF FF FF FF FF
$!
$! Mode Sense Data Length ...... 26
$! Medium Type ................. 00h
$! Device-Specific Parameter ... 00h
$! Block Descriptor Length ..... 8
$! Block Descriptor Data ....... 00 00 00 00 00 00 02 00
$!
$! Page Code ................. 08h
$! Page Name ................. Caching
$! Saveable .................. No
$! Size ...................... 10
$! Hex Data .................. 07 FF FF FF FF FF FF FF
$! FF FF
$!
$! ============================== Peripheral Device Page ======================
$!
$! Issuing 6-byte MODE SENSE QIOW to get current values for page 09h
$!
$! SCSI 6-Byte Mode Sense command returned 20 bytes of data:
$!
$! 000: 13 00 00 08 00 00 00 00 00 00 02 00 09 06 00 00
$! 010: 00 00 00 00
$!
$! Mode Sense Data Length ...... 19
$! Medium Type ................. 00h
$! Device-Specific Parameter ... 00h
$! Block Descriptor Length ..... 8
$! Block Descriptor Data ....... 00 00 00 00 00 00 02 00
$!
$! Page Code ................. 09h
$! Page Name ................. Peripheral Device
$! Saveable .................. No
$! Size ...................... 6
$! Hex Data .................. 00 00 00 00 00 00
$!
$! Issuing 6-byte MODE SENSE QIOW to get changeable values for page 09h
$!
$! SCSI 6-Byte Mode Sense command returned 20 bytes of data:
$!
$! 000: 13 00 00 08 00 00 00 00 00 00 02 00 09 06 00 00
$! 010: 00 00 00 00
$!
$! Mode Sense Data Length ...... 19
$! Medium Type ................. 00h
$! Device-Specific Parameter ... 00h
$! Block Descriptor Length ..... 8
$! Block Descriptor Data ....... 00 00 00 00 00 00 02 00
$!
$! Page Code ................. 09h
$! Page Name ................. Peripheral Device
$! Saveable .................. No
$! Size ...................... 6
$! Hex Data .................. 00 00 00 00 00 00
$!
$! Issuing 10-byte MODE SENSE QIOW to get current values for page 09h
$!
$! SCSI 10-Byte Mode Sense command returned 24 bytes of data:
$!
$! 000: 00 16 00 00 00 00 00 08 00 00 00 00 00 00 02 00
$! 010: 09 06 00 00 00 00 00 00
$!
$! Mode Sense Data Length ...... 22
$! Medium Type ................. 00h
$! Device-Specific Parameter ... 00h
$! Block Descriptor Length ..... 8
$! Block Descriptor Data ....... 00 00 00 00 00 00 02 00
$!
$! Page Code ................. 09h
$! Page Name ................. Peripheral Device
$! Saveable .................. No
$! Size ...................... 6
$! Hex Data .................. 00 00 00 00 00 00
$!
$! Issuing 10-byte MODE SENSE QIOW to get changeable values for page 09h
$!
$! SCSI 10-Byte Mode Sense command returned 24 bytes of data:
$!
$! 000: 00 16 00 00 00 00 00 08 00 00 00 00 00 00 02 00
$! 010: 09 06 00 00 00 00 00 00
$!
$! Mode Sense Data Length ...... 22
$! Medium Type ................. 00h
$! Device-Specific Parameter ... 00h
$! Block Descriptor Length ..... 8
$! Block Descriptor Data ....... 00 00 00 00 00 00 02 00
$!
$! Page Code ................. 09h
$! Page Name ................. Peripheral Device
$! Saveable .................. No
$! Size ...................... 6
$! Hex Data .................. 00 00 00 00 00 00
$!
$! ================================ Control Mode Page =========================
$!
$! Issuing 6-byte MODE SENSE QIOW to get current values for page 0Ah
$!
$! SCSI 6-Byte Mode Sense command returned 20 bytes of data:
$!
$! 000: 13 00 00 08 00 00 00 00 00 00 02 00 0A 06 00 00
$! 010: 00 00 00 00
$!
$! Mode Sense Data Length ...... 19
$! Medium Type ................. 00h
$! Device-Specific Parameter ... 00h
$! Block Descriptor Length ..... 8
$! Block Descriptor Data ....... 00 00 00 00 00 00 02 00
$!
$! Page Code ................. 0Ah
$! Page Name ................. Control Mode
$! Saveable .................. No
$! Size ...................... 6
$! Hex Data .................. 00 00 00 00 00 00
$!
$! Issuing 6-byte MODE SENSE QIOW to get changeable values for page 0Ah
$!
$! SCSI 6-Byte Mode Sense command returned 20 bytes of data:
$!
$! 000: 13 00 00 08 00 00 00 00 00 00 02 00 0A 06 00 00
$! 010: 00 00 00 00
$!
$! Mode Sense Data Length ...... 19
$! Medium Type ................. 00h
$! Device-Specific Parameter ... 00h
$! Block Descriptor Length ..... 8
$! Block Descriptor Data ....... 00 00 00 00 00 00 02 00
$!
$! Page Code ................. 0Ah
$! Page Name ................. Control Mode
$! Saveable .................. No
$! Size ...................... 6
$! Hex Data .................. 00 00 00 00 00 00
$!
$! Issuing 10-byte MODE SENSE QIOW to get current values for page 0Ah
$!
$! SCSI 10-Byte Mode Sense command returned 24 bytes of data:
$!
$! 000: 00 16 00 00 00 00 00 08 00 00 00 00 00 00 02 00
$! 010: 0A 06 00 00 00 00 00 00
$!
$! Mode Sense Data Length ...... 22
$! Medium Type ................. 00h
$! Device-Specific Parameter ... 00h
$! Block Descriptor Length ..... 8
$! Block Descriptor Data ....... 00 00 00 00 00 00 02 00
$!
$! Page Code ................. 0Ah
$! Page Name ................. Control Mode
$! Saveable .................. No
$! Size ...................... 6
$! Hex Data .................. 00 00 00 00 00 00
$!
$! Issuing 10-byte MODE SENSE QIOW to get changeable values for page 0Ah
$!
$! SCSI 10-Byte Mode Sense command returned 24 bytes of data:
$!
$! 000: 00 16 00 00 00 00 00 08 00 00 00 00 00 00 02 00
$! 010: 0A 06 00 00 00 00 00 00
$!
$! Mode Sense Data Length ...... 22
$! Medium Type ................. 00h
$! Device-Specific Parameter ... 00h
$! Block Descriptor Length ..... 8
$! Block Descriptor Data ....... 00 00 00 00 00 00 02 00
$!
$! Page Code ................. 0Ah
$! Page Name ................. Control Mode
$! Saveable .................. No
$! Size ...................... 6
$! Hex Data .................. 00 00 00 00 00 00
$!
$! =========================== Medium Types Supported Page ====================
$!
$! Issuing 6-byte MODE SENSE QIOW to get current values for page 0Bh
$!
$! SCSI 6-Byte Mode Sense command returned 20 bytes of data:
$!
$! 000: 13 00 00 08 00 00 00 00 00 00 02 00 0B 06 00 00
$! 010: 00 00 00 00
$!
$! Mode Sense Data Length ...... 19
$! Medium Type ................. 00h
$! Device-Specific Parameter ... 00h
$! Block Descriptor Length ..... 8
$! Block Descriptor Data ....... 00 00 00 00 00 00 02 00
$!
$! Page Code ................. 0Bh
$! Page Name ................. Medium Types Supported
$! Saveable .................. No
$! Size ...................... 6
$! Hex Data .................. 00 00 00 00 00 00
$!
$! Issuing 6-byte MODE SENSE QIOW to get changeable values for page 0Bh
$!
$! SCSI 6-Byte Mode Sense command returned 20 bytes of data:
$!
$! 000: 13 00 00 08 00 00 00 00 00 00 02 00 0B 06 00 00
$! 010: 00 00 00 00
$!
$! Mode Sense Data Length ...... 19
$! Medium Type ................. 00h
$! Device-Specific Parameter ... 00h
$! Block Descriptor Length ..... 8
$! Block Descriptor Data ....... 00 00 00 00 00 00 02 00
$!
$! Page Code ................. 0Bh
$! Page Name ................. Medium Types Supported
$! Saveable .................. No
$! Size ...................... 6
$! Hex Data .................. 00 00 00 00 00 00
$!
$! Issuing 10-byte MODE SENSE QIOW to get current values for page 0Bh
$!
$! SCSI 10-Byte Mode Sense command returned 24 bytes of data:
$!
$! 000: 00 16 00 00 00 00 00 08 00 00 00 00 00 00 02 00
$! 010: 0B 06 00 00 00 00 00 00
$!
$! Mode Sense Data Length ...... 22
$! Medium Type ................. 00h
$! Device-Specific Parameter ... 00h
$! Block Descriptor Length ..... 8
$! Block Descriptor Data ....... 00 00 00 00 00 00 02 00
$!
$! Page Code ................. 0Bh
$! Page Name ................. Medium Types Supported
$! Saveable .................. No
$! Size ...................... 6
$! Hex Data .................. 00 00 00 00 00 00
$!
$! Issuing 10-byte MODE SENSE QIOW to get changeable values for page 0Bh
$!
$! SCSI 10-Byte Mode Sense command returned 24 bytes of data:
$!
$! 000: 00 16 00 00 00 00 00 08 00 00 00 00 00 00 02 00
$! 010: 0B 06 00 00 00 00 00 00
$!
$! Mode Sense Data Length ...... 22
$! Medium Type ................. 00h
$! Device-Specific Parameter ... 00h
$! Block Descriptor Length ..... 8
$! Block Descriptor Data ....... 00 00 00 00 00 00 02 00
$!
$! Page Code ................. 0Bh
$! Page Name ................. Medium Types Supported
$! Saveable .................. No
$! Size ...................... 6
$! Hex Data .................. 00 00 00 00 00 00
$!
$! ============================= Notch and Partition Page =====================
$!
$! Issuing 6-byte MODE SENSE QIOW to get current values for page 0Ch
$!
$! SCSI 6-Byte Mode Sense command returned 36 bytes of data:
$!
$! 000: 23 00 00 08 00 00 00 00 00 00 02 00 0C 16 00 00
$! 010: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
$! 020: 20 00 00 00
$!
$! Mode Sense Data Length ...... 35
$! Medium Type ................. 00h
$! Device-Specific Parameter ... 00h
$! Block Descriptor Length ..... 8
$! Block Descriptor Data ....... 00 00 00 00 00 00 02 00
$!
$! Page Code ................. 0Ch
$! Page Name ................. Notch and Partition
$! Saveable .................. No
$! Size ...................... 22
$! Hex Data .................. 00 00 00 00 00 00 00 00
$! 00 00 00 00 00 00 00 00 00 00 20 00 00 00
$!
$! Issuing 6-byte MODE SENSE QIOW to get changeable values for page 0Ch
$!
$! SCSI 6-Byte Mode Sense command returned 36 bytes of data:
$!
$! 000: 23 00 00 08 00 00 00 00 00 00 02 00 0C 16 00 00
$! 010: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
$! 020: 00 00 00 00
$!
$! Mode Sense Data Length ...... 35
$! Medium Type ................. 00h
$! Device-Specific Parameter ... 00h
$! Block Descriptor Length ..... 8
$! Block Descriptor Data ....... 00 00 00 00 00 00 02 00
$!
$! Page Code ................. 0Ch
$! Page Name ................. Notch and Partition
$! Saveable .................. No
$! Size ...................... 22
$! Hex Data .................. 00 00 00 00 00 00 00 00
$! 00 00 00 00 00 00 00 00 00 00 00 00 00 00
$!
$! Issuing 10-byte MODE SENSE QIOW to get current values for page 0Ch
$!
$! SCSI 10-Byte Mode Sense command returned 40 bytes of data:
$!
$! 000: 00 26 00 00 00 00 00 08 00 00 00 00 00 00 02 00
$! 010: 0C 16 00 00 00 00 00 00 00 00 00 00 00 00 00 00
$! 020: 00 00 00 00 20 00 00 00
$!
$! Mode Sense Data Length ...... 38
$! Medium Type ................. 00h
$! Device-Specific Parameter ... 00h
$! Block Descriptor Length ..... 8
$! Block Descriptor Data ....... 00 00 00 00 00 00 02 00
$!
$! Page Code ................. 0Ch
$! Page Name ................. Notch and Partition
$! Saveable .................. No
$! Size ...................... 22
$! Hex Data .................. 00 00 00 00 00 00 00 00
$! 00 00 00 00 00 00 00 00 00 00 20 00 00 00
$!
$! Issuing 10-byte MODE SENSE QIOW to get changeable values for page 0Ch
$!
$! SCSI 10-Byte Mode Sense command returned 40 bytes of data:
$!
$! 000: 00 26 00 00 00 00 00 08 00 00 00 00 00 00 02 00
$! 010: 0C 16 00 00 00 00 00 00 00 00 00 00 00 00 00 00
$! 020: 00 00 00 00 00 00 00 00
$!
$! Mode Sense Data Length ...... 38
$! Medium Type ................. 00h
$! Device-Specific Parameter ... 00h
$! Block Descriptor Length ..... 8
$! Block Descriptor Data ....... 00 00 00 00 00 00 02 00
$!
$! Page Code ................. 0Ch
$! Page Name ................. Notch and Partition
$! Saveable .................. No
$! Size ...................... 22
$! Hex Data .................. 00 00 00 00 00 00 00 00
$! 00 00 00 00 00 00 00 00 00 00 00 00 00 00
$!
$! =============================== Vendor Specific Page =======================
$!
$! Issuing 6-byte MODE SENSE QIOW to get current values for page 00h
$!
$! SCSI 6-Byte Mode Sense command returned 12 bytes of data:
$!
$! 000: 0B 00 00 08 00 00 00 00 00 00 02 00
$!
$! Mode Sense Data Length ...... 11
$! Medium Type ................. 00h
$! Device-Specific Parameter ... 00h
$! Block Descriptor Length ..... 8
$! Block Descriptor Data ....... 00 00 00 00 00 00 02 00
$!
$! Issuing 6-byte MODE SENSE QIOW to get changeable values for page 00h
$!
$! SCSI 6-Byte Mode Sense command returned 12 bytes of data:
$!
$! 000: 0B 00 00 08 00 00 00 00 00 00 02 00
$!
$! Mode Sense Data Length ...... 11
$! Medium Type ................. 00h
$! Device-Specific Parameter ... 00h
$! Block Descriptor Length ..... 8
$! Block Descriptor Data ....... 00 00 00 00 00 00 02 00
$!
$! Issuing 10-byte MODE SENSE QIOW to get current values for page 00h
$!
$! SCSI 10-Byte Mode Sense command returned 16 bytes of data:
$!
$! 000: 00 0E 00 00 00 00 00 08 00 00 00 00 00 00 02 00
$!
$! Mode Sense Data Length ...... 14
$! Medium Type ................. 00h
$! Device-Specific Parameter ... 00h
$! Block Descriptor Length ..... 8
$! Block Descriptor Data ....... 00 00 00 00 00 00 02 00
$!
$! Issuing 10-byte MODE SENSE QIOW to get changeable values for page 00h
$!
$! SCSI 10-Byte Mode Sense command returned 16 bytes of data:
$!
$! 000: 00 0E 00 00 00 00 00 08 00 00 00 00 00 00 02 00
$!
$! Mode Sense Data Length ...... 14
$! Medium Type ................. 00h
$! Device-Specific Parameter ... 00h
$! Block Descriptor Length ..... 8
$! Block Descriptor Data ....... 00 00 00 00 00 00 02 00
$!
$!

On 2022-04-28, Volker Halle <volker_halle@hotmail.com> wrote:
> the value 132 is the system service status code:
>
> VSIAXP $ exit 132 %SYSTEM-F-DEVOFFLINE, device is not in configuration
> or not available
>
> Here is the SCSI_INFO data from an emulated DGA device on a CHARON-AXP
> emulator:

Thank you Volker! Having all of the good responses from a working target
could go a long way to working out what's required to support VMS.

Lots to look over, but I found that some of the sg3-utils tools on Linux
can help decode messages from hex dumps of the raw data, so that at
least is a lot quicker then doing it all by hand.

Thanks,
Matthew

Progress!!!

After looking at the data from Volker's system, the most obvious
difference in the initial standard INQUIRY response is that his DGA
device was reporting SCSI version 2. FreeBSD's SCSI target
implementation reports SPC5. SPC5 appears to be too new for OpenVMS to
accept. I built a new kernel which reports an older version (after
experimentation, I don't need to go all the way down to SCSI 2, I just
need to go down one version to SPC4) and... the device shows as 'Online'
in OpenVMS!

After that, the SCSI_INFO output appears largely similar to Volker's --
all of the data for the various sense pages is listed out.

Hurdles remain, though: when I try to initialize the volume, I get the
error: %INIT-F-MEDOFL, medium is offline

BUT... I see in the logs on the FreeBSD side that VMS was repeatedly
issuing READ LONG(10) commands (operation code 0x3e), and it looks like
FreeBSD hasn't implemented that command. In the source, I see it's just
stubbed out to always return an illegal request check condition.

At least the problem is clear. I'll have to look into what it takes to
implement support for the READ LONG(10) command, and see what
command(s), if any, it gets stuck on next.

Thanks for everyone's input thus far. Now that I'm past the problem of
OpenVMS being willing to even TRY to work with the device, it looks like
at this point it will just be a SCSI command troubleshooting and
implementation exercise. That could take time as I'm entirely unfamiliar
with this FreeBSD codebase, but I'm optimistic it may be possible when I
have some time I can dedicate to it.

Thanks,
Matthew

On Thursday, 28 April 2022 at 10:02:56 UTC+1, Matthew R. Wilson wrote:
> Progress!!!
>
> After looking at the data from Volker's system, the most obvious
> difference in the initial standard INQUIRY response is that his DGA
> device was reporting SCSI version 2. FreeBSD's SCSI target
> implementation reports SPC5. SPC5 appears to be too new for OpenVMS to
> accept. I built a new kernel which reports an older version (after
> experimentation, I don't need to go all the way down to SCSI 2, I just
> need to go down one version to SPC4) and... the device shows as 'Online'
> in OpenVMS!
>
> After that, the SCSI_INFO output appears largely similar to Volker's --
> all of the data for the various sense pages is listed out.
>
> Hurdles remain, though: when I try to initialize the volume, I get the
> error: %INIT-F-MEDOFL, medium is offline
>
> BUT... I see in the logs on the FreeBSD side that VMS was repeatedly
> issuing READ LONG(10) commands (operation code 0x3e), and it looks like
> FreeBSD hasn't implemented that command. In the source, I see it's just
> stubbed out to always return an illegal request check condition.
>
> At least the problem is clear. I'll have to look into what it takes to
> implement support for the READ LONG(10) command, and see what
> command(s), if any, it gets stuck on next.
>
> Thanks for everyone's input thus far. Now that I'm past the problem of
> OpenVMS being willing to even TRY to work with the device, it looks like
> at this point it will just be a SCSI command troubleshooting and
> implementation exercise. That could take time as I'm entirely unfamiliar
> with this FreeBSD codebase, but I'm optimistic it may be possible when I
> have some time I can dedicate to it.
>
> Thanks,
> Matthew

READL (aka "read long") and the equivalent write command are important parts of VMS volume shadowing - so important they're even mentioned in the Software Product Description. Have a read (if you haven't already done so), see if it helps you work out what's going on, and whether it matters for your needs or not.

E.g. this is one snippet from the VSIVMS Volume Shadowing Guide at e.g. https://vmssoftware.com/docs/VSI_VOLUME_SHAD_GD.pdf section 1.3.2 Supported Devices:

"SCSI disks that do not implement READL and WRITEL have limited support because these
disks do not provide for shadowing data repair (disk bad block errors) features. Such disks can
cause members to be removed from the shadow set, if certain error conditions arise that cannot
be corrected. See Section 4.11.5.1 for how to determine if a SCSI disk supports READL and
WRITEL commands."

There are other potentially relevant references in that manual too e.g. MOUNT /OVERRIDE=NO_FORCED_ERROR.

Have a lot of fun.

On 2022-04-28, John Wallace <johnwallace4@yahoo.co.uk> wrote:
> On Thursday, 28 April 2022 at 10:02:56 UTC+1, Matthew R. Wilson wrote:
>> VMS was repeatedly issuing READ LONG(10) commands (operation code
>> 0x3e), and it looks like FreeBSD hasn't implemented that command. In
>> the source, I see it's just stubbed out to always return an illegal
>> request check condition.
>>
>> At least the problem is clear. I'll have to look into what it takes
>> to implement support for the READ LONG(10) command, and see what
>> command(s), if any, it gets stuck on next.
>
> READL (aka "read long") and the equivalent write command are important
> parts of VMS volume shadowing - so important they're even mentioned in
> the Software Product Description. Have a read (if you haven't already
> done so), see if it helps you work out what's going on, and whether it
> matters for your needs or not.
>
> E.g. this is one snippet from the VSIVMS Volume Shadowing Guide at
> e.g. https://vmssoftware.com/docs/VSI_VOLUME_SHAD_GD.pdf section 1.3.2
> Supported Devices:

Interesting. The wording in the Volume Shadowing Guide seem to imply
that VMS itself would work with devices that don't support READ/WRITE
LONG, but you shouldn't use them with Volume Shadowing.

It seems like for FC devices, the support isn't optional. That may make
sense knowing how important it is for Volume Shadowing... due to the
fact that FC targets are often available via multiple paths and are
likely shared between different systems, the same reasons Volume
Shadowing depends on READ/WRITE LONG may be relevant for the common FC
configurations.

The READ LONG and WRITE LONG commands have been removed from the latest
SCSI standard. I wonder if that's why VMS refused to try to work with my
target when it was reporting that it was a version SPC-5
implementation... VMS may know the READ/WRITE LONG commands are no
longer in the standard and so rejects the new version. (Or it may have
no special knowledge of SPC-5 and later at all, and just plays it safe
and refuses it because it only knows about SPC-4 and below.)

Thanks,
Matthew

On 2022-04-28, Matthew R. Wilson <mwilson@mattwilson.org> wrote:
> Hurdles remain, though: when I try to initialize the volume, I get the
> error: %INIT-F-MEDOFL, medium is offline
>
> BUT... I see in the logs on the FreeBSD side that VMS was repeatedly
> issuing READ LONG(10) commands (operation code 0x3e), and it looks like
> FreeBSD hasn't implemented that command. In the source, I see it's just
> stubbed out to always return an illegal request check condition.
>
> At least the problem is clear. I'll have to look into what it takes to
> implement support for the READ LONG(10) command, and see what
> command(s), if any, it gets stuck on next.

After further experimentation, I think the READ LONG exceptions are red
herrings.

I think VMS is issuing the READ LONG commands to determine if the target
supports the command, and if so, what the correct byte transfer length
value is. I don't think the fact that all the commands fail is fatal.
After going through that process, the flags in the SDA SHOW DEVICE
command include "nofe", which the Volume Shadowing guide tells us means
the device doesn't support the READ/WRITE LONG commands.

After all those commands fail during the attempt to initialize the
device, VMS issues a few 1-block read and write commands. Then it pauses
for a bit, cancels all requests and says the medium is offline.

So... I don't think it's the READ LONG stuff that's fatal, I think
there's some other mystery problem I need to figure out. It almost seems
like the last READ it sends is timing out, but that doesn't really seem
possible. If I issue the same READ myself against the target, it returns
right away, just as the previous reads did. I need to look more closely
and see if there was an earlier SENSE command or something that wasn't
being satisfied.

In any case... I understand READ/WRITE LONG is critical for proper
operation of Volume Shadowing, but I don't think it's what's preventing
OpenVMS from working with a fibre channel target.

Thanks,
Matthew

Matthew,

consider to use the DKLOG SDA extension to find out the details about the IOs done during the INIT command:

$ ANALYZE/SYSTEM
SDA> DKLOG START $1$DGAx:
SDA> SPAWN INIT $1$DGA1: TEST
SDA> DKLOG STOP $1$DGAx:
SDA> DKLOG SHOW $1$DGAx:
....

Maybe compare that output with a working INIT command on some other disk.

Volker.

You might also try bumping FreeBSD down to SPC3 to see what happens if you're not having any other progress.

I recall having to go through some protocol debugging with HPE when they added SPC4 support for the BL860 SAS SSDs which we wanted to use. There may be some nuances of the SPC4 protocol implementation in FreeBSD that they aren't prepared to deal with.

I thought I remember someone telling me that READL/WRITEL was mandatory for SCSI and FC operations, not just for Shadowing, but that may be my faulty memory.

David

SUCCESS!

It turns out there was another confounding factor in my experiments:
dodgy hardware.

Not sure if it's a dirty optic, failing SFP port, or what. But I
switched to doing some heavy I/O testing by installing Linux on the
Itanium system and using the same FC targets... and Linux started
logging all sort of dropped frame messages on the console. This after I
started realizing I was encountering some very odd seemingly "stateful"
behavior in OpenVMS when trying to use the FC target: sometimes commands
would work, sometimes they wouldn't, sometimes they'd hang for a while,
etc., all seemingly without reason. Should have suspected a lower-level
hardware problem earlier...

I switched to a second FC HBA I have for the Itanium, switched SFPs in
the SAN switch, and while I still can't get the errors entirely
eliminated (I don't have anything to actually clean the optics here at
home with me at the moment), I can get through a couple GBs of data
transfer in Linux at a time without errors. So I figured I'd try from
VMS again... and it works perfectly. INIT runs instantly, I can mount
the volume, I can write and read data, etc.

<sigh>

Always something dumb/simple.

In the end, the *only* change I needed to make was to have the FreeBSD
target emulation report a lower SCSI version. I'm having luck with
SCSI-3.

For those playing along at home, around line 10211 of sys/cam/ctl/ctl.c,
you can change:

inq_ptr->version = SCSI_REV_SPC5;
to
inq_ptr->version = SCSI_REV_SPC;

Then rebuild the FreeBSD kernel and OpenVMS appears to be happy.

When defining your LUNs in FreeBSD, you must also set option ident_info
to a four-byte number to control the UDID; for example 0x00000007 will
make the LUN appear as $1$DGA7 in VMS.

I still don't trust the FC connectivity until I can repeat the testing
from Linux without any interface errors, but with things mostly
reliable, I'm happy to report OpenVMS is working well with the FreeBSD
SAN volumes so far.

Thank you for all of your input and help throughout this process! I
ended up going on a wild goose chase with some of the SCSI behavior that
was easily explained away by hardware problems, but at least I learned a
lot.

Thanks,
Matthew

On 04/30/22 18:48, dthi...@gmail.com wrote:
> Oh yeah; check the FreeBSD FC disk block size. OpenVMS may not be able to cope with anything larger than the original 512 byte blocks..

FreeBSD disk block size is always 512 bytes. The host adapter
may use larger block sizes as part of the error handling scheme,
but FreeBSD would never see that

You could try downgrading to NFS V3, rather than 4, but
unless you can verify that the local drive under vms can be
written to and read from, any higher level protocol tests
eg: NFS are a waste of time.

Too many variables, do the basics first...

Chris