My computer has two HDD and wifi. suddenly, about 48 hours ago, wifi
has stopped working for my phone and (as a result) for my tablet, which
does not have its own modem. The computer itself seems not to be
affected. Running the system locally from a SIM from another ISP fixes
everything. I have rebooted the modem. On it, the WLAN light is
extinguished.

Is there a carrier that rides on the main Broadband signal? I recall
something like this happening back in the Flintstones (ADSL) era, but it
took out everything. It was something like having a bare carrier with
no data riding on it.

Doug.

On Mon, 28 Jun 2021 05:14:15 +1000, Doug Laidlaw wrote:
> My computer has two HDD and wifi. suddenly, about 48 hours ago, wifi
> has stopped working for my phone and (as a result) for my tablet, which
> does not have its own modem. The computer itself seems not to be
> affected. Running the system locally from a SIM from another ISP fixes
> everything. I have rebooted the modem. On it, the WLAN light is
> extinguished.

I suggest to you that the WLAN led comes on when the modem gets
assigned a lease from the ISP dhcp server.

On 28/6/21 5:46 am, Bit Twister wrote:
> On Mon, 28 Jun 2021 05:14:15 +1000, Doug Laidlaw wrote:
>> My computer has two HDD and wifi. suddenly, about 48 hours ago, wifi
>> has stopped working for my phone and (as a result) for my tablet, which
>> does not have its own modem. The computer itself seems not to be
>> affected. Running the system locally from a SIM from another ISP fixes
>> everything. I have rebooted the modem. On it, the WLAN light is
>> extinguished.
>
> I suggest to you that the WLAN led comes on when the modem gets
> assigned a lease from the ISP dhcp server.
>
Yes, a lot of shoddy thinking on my part. The computer runs because it
is on Ethernet. A separate SIM works because it bypasses the blockage.
So is it a problem caused by the ISP, not assigning a lease?

On Mon, 28 Jun 2021 06:29:39 +1000, Doug Laidlaw wrote:
> On 28/6/21 5:46 am, Bit Twister wrote:
>> On Mon, 28 Jun 2021 05:14:15 +1000, Doug Laidlaw wrote:
>>> My computer has two HDD and wifi. suddenly, about 48 hours ago, wifi
>>> has stopped working for my phone and (as a result) for my tablet, which
>>> does not have its own modem. The computer itself seems not to be
>>> affected. Running the system locally from a SIM from another ISP fixes
>>> everything. I have rebooted the modem. On it, the WLAN light is
>>> extinguished.
>>
>> I suggest to you that the WLAN led comes on when the modem gets
>> assigned a lease from the ISP dhcp server.
>>
> Yes, a lot of shoddy thinking on my part. The computer runs because it
> is on Ethernet. A separate SIM works because it bypasses the blockage.
> So is it a problem caused by the ISP, not assigning a lease?
>

I can not say exactly why you are not getting the WLAN led.
Possibilities:
Connection to gateway is down
Gateway is down
Connection to dhcp servers is down
dhcp servers down
maybe dns causing dhcp server problems.

Only way for you to know is to use ping to test each point of
contact.

I can suggest writing a script say ck_network, that pings each
point to tell you exactly where the failure is.
Of course it helps that everything is working when debugging
the script.

You would look at modem status pages and use "traceroute -I yahoo.com"
to get ip address to ping.

Think about it, each node in the internet path has a WAN and LAN side.
I find it helpful to assign static ip to all devices on my LAN.
Makes script code a bit easier.

If you can not ping
o your node LAN ip your computer nic is down,
o your router LAN ip, router/cable is broke
o your router WAN ip, router is broke or did not get ip
from modem,
o your modem LAN ip, cable to router from modem is bad or
either device is broke.
o your modem WAN ip, modem is bad or not assigned an ip.
o isp gateway LAN ip, gateway or connection to isp gateway is down
o isp dns server, connection or dns server is down
o yahoo.com and gmail.com, access to Internet is down.

wget -qO - http://icanhazip.com can get your modem WAN ip.

On 6/27/2021 2:16 PM, Bit Twister wrote:
> On Mon, 28 Jun 2021 06:29:39 +1000, Doug Laidlaw wrote:
>> On 28/6/21 5:46 am, Bit Twister wrote:
>>> On Mon, 28 Jun 2021 05:14:15 +1000, Doug Laidlaw wrote:
>>>> My computer has two HDD and wifi. suddenly, about 48 hours ago, wifi
>>>> has stopped working for my phone and (as a result) for my tablet, which
>>>> does not have its own modem. The computer itself seems not to be
>>>> affected. Running the system locally from a SIM from another ISP fixes
>>>> everything. I have rebooted the modem. On it, the WLAN light is
>>>> extinguished.
>>>
>>> I suggest to you that the WLAN led comes on when the modem gets
>>> assigned a lease from the ISP dhcp server.
>>>
>> Yes, a lot of shoddy thinking on my part. The computer runs because it
>> is on Ethernet. A separate SIM works because it bypasses the blockage.
>> So is it a problem caused by the ISP, not assigning a lease?
>>
>
> I can not say exactly why you are not getting the WLAN led.
> Possibilities:
> Connection to gateway is down
> Gateway is down
> Connection to dhcp servers is down
> dhcp servers down
> maybe dns causing dhcp server problems.
>
> Only way for you to know is to use ping to test each point of
> contact.
>
>

If the WAN LED is out, then he's got local connectivity, but he is not
connected to whatever is on the other side of the gateway/router.

I would first suggest rebooting the gateway. If that doesn't help, I
would call the ISP's customer service, asking if there's an outage.

On 28/6/21 7:25 am, red floyd wrote:
> On 6/27/2021 2:16 PM, Bit Twister wrote:
>> On Mon, 28 Jun 2021 06:29:39 +1000, Doug Laidlaw wrote:
>>> On 28/6/21 5:46 am, Bit Twister wrote:
>>>> On Mon, 28 Jun 2021 05:14:15 +1000, Doug Laidlaw wrote:
>>>>> My computer has two HDD and wifi.  suddenly, about 48 hours ago,  wifi
>>>>> has stopped working for my phone and (as a result) for my tablet,
>>>>> which
>>>>> does not have its own modem.  The computer itself seems not to be
>>>>> affected.  Running the system locally from a SIM from another ISP
>>>>> fixes
>>>>> everything.  I have rebooted the modem.  On it, the WLAN light is
>>>>> extinguished.
>>>>
>>>> I suggest to you that the WLAN led comes on when the modem gets
>>>> assigned a lease from the ISP dhcp server.
>>>>
>>> Yes, a lot of shoddy thinking on my part.  The computer runs because it
>>> is on Ethernet.  A separate SIM works because it bypasses the blockage.
>>> So is it a problem caused by the ISP, not assigning a lease?
>>>
>>
>> I can not say exactly why you are not getting the WLAN led.
>> Possibilities:
>>      Connection to gateway is down
>>      Gateway is down
>>      Connection to dhcp servers is down
>>      dhcp servers down
>>      maybe dns causing dhcp server problems.
>>
>> Only way for you to know is to use ping to test each point of
>> contact.

>
> If the WAN LED is out, then he's got local connectivity, but he is not
> connected to whatever is on the other side of the gateway/router.
>
> I would first suggest rebooting the gateway.  If that doesn't help, I
> would call the ISP's customer service, asking if there's an outage.
>
I have a ticket with the ISP.

The answer was very simple, really. Our broadband connection is always
dropping out. They are advising people to put the NBN router to one
side and substitute a different one. When this happens, rebooting the
router MAY help.
The switches are on the back of the edge of the router, and not easily
accessible. Immediately above the power switch is an on-off switch for
the WLAN. I had accidentally turned the WLAN off! I switched it on
there, and everything is back to normal.

On Mon, 28 Jun 2021 07:39:40 +1000, Doug Laidlaw wrote:

>
> The answer was very simple, really. Our broadband connection is always
> dropping out.

Then I can recommend creating/running a ch_network script to
run in hourly cron to save you some trouble shooting time.