I've always been able to log in to my cable modem,
a Motorola. Just now, I no longer can. Nothing's changed
that I know of (famous last words...). I log in to look
at the error rates to assure myself that the connection
is not deteriorating. I also changed the default password.

The modem's IP address is 192.168.100.1. Linking to that
address times out. The net mask in the router is ff ff ff 00.

Any ideas?

In article <MPG.40402d0456462ff89896ae@news.eternal-september.org>,
jason_warren@INVALID.ieee.org says...
>
> I've always been able to log in to my cable modem,
> a Motorola. Just now, I no longer can. Nothing's changed
> that I know of (famous last words...). I log in to look
> at the error rates to assure myself that the connection
> is not deteriorating. I also changed the default password.
>
> The modem's IP address is 192.168.100.1. Linking to that
> address times out. The net mask in the router is ff ff ff 00.
>
> Any ideas?

PS - I tried all this on 3 different browsers on each of two computers
so I don't think browser security settings are the problem...

Jason wrote:
> I've always been able to log in to my cable modem,
> a Motorola. Just now, I no longer can. Nothing's changed
> that I know of (famous last words...). I log in to look
> at the error rates to assure myself that the connection
> is not deteriorating. I also changed the default password.
>
> The modem's IP address is 192.168.100.1. Linking to that
> address times out. The net mask in the router is ff ff ff 00.
>
> Any ideas?

Did you reset the modem to factory specs?

On 2/21/2024 3:36 PM, jason_warren@ieee.org wrote:
> In article <MPG.40402d0456462ff89896ae@news.eternal-september.org>,
> jason_warren@INVALID.ieee.org says...
>>
>> I've always been able to log in to my cable modem,
>> a Motorola. Just now, I no longer can. Nothing's changed
>> that I know of (famous last words...). I log in to look
>> at the error rates to assure myself that the connection
>> is not deteriorating. I also changed the default password.
>>
>> The modem's IP address is 192.168.100.1. Linking to that
>> address times out. The net mask in the router is ff ff ff 00.
>>
>> Any ideas?
>
> PS - I tried all this on 3 different browsers on each of two computers
> so I don't think browser security settings are the problem...

did you run ipconfig in the command prompt to make sure the default
gateway is the same?

--
Stand With Israel!

On 2/21/2024 4:36 PM, jason_warren@ieee.org wrote:
> In article <MPG.40402d0456462ff89896ae@news.eternal-september.org>,
> jason_warren@INVALID.ieee.org says...
>>
>> I've always been able to log in to my cable modem,
>> a Motorola. Just now, I no longer can. Nothing's changed
>> that I know of (famous last words...). I log in to look
>> at the error rates to assure myself that the connection
>> is not deteriorating. I also changed the default password.
>>
>> The modem's IP address is 192.168.100.1. Linking to that
>> address times out. The net mask in the router is ff ff ff 00.
>>
>> Any ideas?
>
> PS - I tried all this on 3 different browsers on each of two computers
> so I don't think browser security settings are the problem...
>

What is your PC IP address and netmask ?

If I was on 192.168.1.2 and I tried to reach 192.168.100.1 ,
that would not work, because I've set up the DHCP on the router
to give out a netmask of /24 (ff ff ff 00). I would need to
change to /16 (ff ff 00 00) so comms between subnets would work.
I normally do things like that temporarily, and after a reboot,
all is back to siloed /24 country.

https://www.digitalcitizen.life/wp-content/uploads/2022/10/subnet_mask-16.png

( https://www.digitalcitizen.life/change-subnet-mask-windows-10/ )

# This sets a temporary netmask good for the remainder of the session (whatever that means).

Get-NetAdapter -physical # Obtain IfIndex for the PC interface needing the fix. "11" in this case.

Ethernet 3 RealTek Network Connec... 11 Up AA-BB-CC-DD-EE-FF 1 Gbps

Set-NetIPAddress -InterfaceIndex 11 -PrefixLength 16

After that, I should be able to reach the device on the other subnet.

Ping relies on ICMP, and it's possible to disable just the ping
portion of ICMP, or disable ICMP completely. If the router firmware
was updated, or some config info was pushed out from the ISP end,
that could result in a change to "ping" response. But you should
still be able to contact the device. Disabling ICMP completely,
prevents proper handling of fragmentation of packets and different
MTUs on different pieces of equipment. My former ISP did that
to their email server one day (no warning), with comical results.
And when I phoned the twirps and described my fault isolation and
conclusion about what they'd done, I got the usual "deny deny deny"
behavior. That's part of the reason they're my former ISP.
(Fragmentation issues can be spotted by sending short or long
text emails, and the long emails, the interface "freezes" when
you try to send the long email. That's a sign.)

"Ping" is "8" in the table. If you don't want attacks based
upon "ping" response, just the ping can be turned off and the
rest of ICMP left running.

https://en.wikipedia.org/wiki/Internet_Control_Message_Protocol

Paul

Jason wrote on 2/21/24 1:54 PM:
> I've always been able to log in to my cable modem,
> a Motorola. Just now, I no longer can. Nothing's changed
> that I know of (famous last words...). I log in to look
> at the error rates to assure myself that the connection
> is not deteriorating. I also changed the default password.
>
> The modem's IP address is 192.168.100.1. Linking to that
> address times out. The net mask in the router is ff ff ff 00.
>
> Any ideas?
>
What 3 browsers did you try using?
Your issue may be security related(SSL,TLS SMB)

--
....w¡ñ§±¤ñ

In article <ur63cp$3ekdt$1@dont-email.me>, Paul@Houston.Texas says...
>
> Jason wrote:
> > I've always been able to log in to my cable modem,
> > a Motorola. Just now, I no longer can. Nothing's changed
> > that I know of (famous last words...). I log in to look
> > at the error rates to assure myself that the connection
> > is not deteriorating. I also changed the default password.
> >
> > The modem's IP address is 192.168.100.1. Linking to that
> > address times out. The net mask in the router is ff ff ff 00.
> >
> > Any ideas?
>
> Did you reset the modem to factory specs?

Yes. I reset it with a paper clip. Nothing changed.

In article <ur6418$3emdm$1@dont-email.me>, wolverine01@charter.net
says...
>
> On 2/21/2024 3:36 PM, jason_warren@ieee.org wrote:
> > In article <MPG.40402d0456462ff89896ae@news.eternal-september.org>,
> > jason_warren@INVALID.ieee.org says...
> >>
> >> I've always been able to log in to my cable modem,
> >> a Motorola. Just now, I no longer can. Nothing's changed
> >> that I know of (famous last words...). I log in to look
> >> at the error rates to assure myself that the connection
> >> is not deteriorating. I also changed the default password.
> >>
> >> The modem's IP address is 192.168.100.1. Linking to that
> >> address times out. The net mask in the router is ff ff ff 00.
> >>
> >> Any ideas?
> >
> > PS - I tried all this on 3 different browsers on each of two computers
> > so I don't think browser security settings are the problem...
>
> did you run ipconfig in the command prompt to make sure the default
> gateway is the same?

I did. All looked correct.

On Thu, 22 Feb 2024 10:06:42 -0500, "jason_warren@ieee.org"
<jason_warren@ieee.org> wrote:

>In article <ur63cp$3ekdt$1@dont-email.me>, Paul@Houston.Texas says...
>>
>> Jason wrote:
>> > I've always been able to log in to my cable modem,
>> > a Motorola. Just now, I no longer can. Nothing's changed
>> > that I know of (famous last words...). I log in to look
>> > at the error rates to assure myself that the connection
>> > is not deteriorating. I also changed the default password.
>> >
>> > The modem's IP address is 192.168.100.1. Linking to that
>> > address times out. The net mask in the router is ff ff ff 00.
>> >
>> > Any ideas?
>>
>> Did you reset the modem to factory specs?
>
>Yes. I reset it with a paper clip. Nothing changed.

Maybe your cable company sent a firmware update and blocked access? I know
I used to be able to log on to my cable modem to reset it but Spectrum now
blocks access on newer modems.

EGK wrote:
> On Thu, 22 Feb 2024 10:06:42 -0500, "jason_warren@ieee.org"
> <jason_warren@ieee.org> wrote:
>
>> In article <ur63cp$3ekdt$1@dont-email.me>, Paul@Houston.Texas says...
>>>
>>> Jason wrote:
>>>> I've always been able to log in to my cable modem,
>>>> a Motorola. Just now, I no longer can. Nothing's changed
>>>> that I know of (famous last words...). I log in to look
>>>> at the error rates to assure myself that the connection
>>>> is not deteriorating. I also changed the default password.
>>>>
>>>> The modem's IP address is 192.168.100.1. Linking to that
>>>> address times out. The net mask in the router is ff ff ff 00.
>>>>
>>>> Any ideas?
>>>
>>> Did you reset the modem to factory specs?
>>
>> Yes. I reset it with a paper clip. Nothing changed.
>
> Maybe your cable company sent a firmware update and blocked access? I know
> I used to be able to log on to my cable modem to reset it but Spectrum now
> blocks access on newer modems.

Run a port scan to see which ports are open. You might find telnet, or
for HTTPS. There may be ports dedicated to a proprietary configuration
utility.

--
Graham J

On 2/21/2024 2:54 PM, Jason wrote:
> I've always been able to log in to my cable modem,
> a Motorola. Just now, I no longer can. Nothing's changed
> that I know of (famous last words...). I log in to look
> at the error rates to assure myself that the connection
> is not deteriorating. I also changed the default password.
>
> The modem's IP address is 192.168.100.1. Linking to that
> address times out. The net mask in the router is ff ff ff 00.
>
> Any ideas?
>
Try plugging a PC directly into the cable modem, verify you have
internet access, then try to log into the cable modem. If it works then
I strongly suspect something in your router is blocking access to the
cable modem.

If a direct Ethernet cable does not let you log into the modem then try
temporarily disabling all Firewalls and anti-virus software on the PC
and see if that works. If it does then you are on your way to
identifying the culprit.

Do a RESET !

KenW

GlowingBlueMist wrote:
> On 2/21/2024 2:54 PM, Jason wrote:
>> I've always been able to log in to my cable modem,
>> a Motorola. Just now, I no longer can. Nothing's changed
>> that I know of (famous last words...). I log in to look
>> at the error rates to assure myself that the connection
>> is not deteriorating. I also changed the default password.
>>
>> The modem's IP address is 192.168.100.1. Linking to that
>> address times out. The net mask in the router is ff ff ff 00.
>>
>> Any ideas?
>>
> Try plugging a PC directly into the cable modem, verify you have
> internet access, then try to log into the cable modem.  If it works then
> I strongly suspect something in your router is blocking access to the
> cable modem.
>
> If a direct Ethernet cable does not let you log into the modem then try
> temporarily disabling all Firewalls and anti-virus software on the PC
> and see if that works.  If it does then you are on your way to
> identifying the culprit.

Is this a combined router and cable modem? Or are there two separate
devices?

Disconnect modem from cable supplier.

Apply factory reset. This should revert it to its original stage when
you first got it.

Connect your PC using the Ethernet cable; you should get access.
Continue to monitor the connection status so you can see if anything changes

Then connect the modem to the cable supplier. After a minute or two you
should get internet access - check using a different browser window.
You might have to apply a username and password for the WAN connection -
what did you do when this was first set up?

You may find the status is no longer available. This might be because
the ISP sees that your modem is out of date and sends the new firmware
immediately. You might see it reboot a couple of times.

--
Graham J

On 02/22/2024 3:13 PM, Graham J wrote:
> GlowingBlueMist wrote:
>> On 2/21/2024 2:54 PM, Jason wrote:
>>> I've always been able to log in to my cable modem,
>>> a Motorola. Just now, I no longer can. Nothing's changed
>>> that I know of (famous last words...). I log in to look
>>> at the error rates to assure myself that the connection
>>> is not deteriorating. I also changed the default password.
>>>
>>> The modem's IP address is 192.168.100.1. Linking to that
>>> address times out. The net mask in the router is ff ff ff 00.
>>>
>>> Any ideas?
>>>
>> Try plugging a PC directly into the cable modem, verify you have
>> internet access, then try to log into the cable modem.  If it works
>> then I strongly suspect something in your router is blocking access to
>> the cable modem.
>>
>> If a direct Ethernet cable does not let you log into the modem then
>> try temporarily disabling all Firewalls and anti-virus software on the
>> PC and see if that works.  If it does then you are on your way to
>> identifying the culprit.
>
> Is this a combined router and cable modem?  Or are there two separate
> devices?
>
> Disconnect modem from cable supplier.
>
> Apply factory reset.  This should revert it to its original stage when
> you first got it.
>
> Connect your PC using the Ethernet cable; you should get access.
> Continue to monitor the connection status so you can see if anything
> changes
>
> Then connect the modem to the cable supplier.  After a minute or two you
> should get internet access - check using a different browser window. You
> might have to apply a username and password for the WAN connection -
> what did you do when this was first set up?
>
> You may find the status is no longer available.  This might be because
> the ISP sees that your modem is out of date and sends the new firmware
> immediately.  You might see it reboot a couple of times.
>
>
>
In router/modems I have had, if I did a reset to factory setting the
pass word to access the router/modem was reset also. The name of the
router would also be returned to what came form the factory
If yours did as the ones I have had the password should be on a sticker
on the case and probably in the back. The two most common router IPs
from the factory are 192.168.1.1 and 192.168.0.1.

In article <2epeti1695iik2quktbascss2p7h3rdnjh@4ax.com>,
memyself@null.net says...

> Maybe your cable company sent a firmware update and blocked access? I know
> I used to be able to log on to my cable modem to reset it but Spectrum now
> blocks access on newer modems.

Hmmm...I have Spectrum service. I'll ask.

In article <4l9fti9vmas71ivpc7m2cisb5vb3okhaa4@4ax.com>, ken1943
@invalid.net says...
>
> Do a RESET !
>
>
> KenW

That was the first thing I tried...didn't help

In article <ur89sv$2dgp$1@dont-email.me>, nobody@nowhere.co.uk says...
>
> GlowingBlueMist wrote:
> > On 2/21/2024 2:54 PM, Jason wrote:
> >> I've always been able to log in to my cable modem,
> >> a Motorola. Just now, I no longer can. Nothing's changed
> >> that I know of (famous last words...). I log in to look
> >> at the error rates to assure myself that the connection
> >> is not deteriorating. I also changed the default password.
> >>
> >> The modem's IP address is 192.168.100.1. Linking to that
> >> address times out. The net mask in the router is ff ff ff 00.
> >>
> >> Any ideas?
> >>
> > Try plugging a PC directly into the cable modem, verify you have
> > internet access, then try to log into the cable modem.  If it works then
> > I strongly suspect something in your router is blocking access to the
> > cable modem.
> >
> > If a direct Ethernet cable does not let you log into the modem then try
> > temporarily disabling all Firewalls and anti-virus software on the PC
> > and see if that works.  If it does then you are on your way to
> > identifying the culprit.
>
> Is this a combined router and cable modem? Or are there two separate
> devices?
>
> Disconnect modem from cable supplier.
>
> Apply factory reset. This should revert it to its original stage when
> you first got it.
>
> Connect your PC using the Ethernet cable; you should get access.
> Continue to monitor the connection status so you can see if anything changes
>
> Then connect the modem to the cable supplier. After a minute or two you
> should get internet access - check using a different browser window.
> You might have to apply a username and password for the WAN connection -
> what did you do when this was first set up?
>
> You may find the status is no longer available. This might be because
> the ISP sees that your modem is out of date and sends the new firmware
> immediately. You might see it reboot a couple of times.

The modem (Motorola DOCSIS 3.1) and the router (Linksys mesh). The modem
is half a year old and the router s/w is up to date.

Today's experiment is to connect my laptop directly to
the modem. That's worked before.

On Fri, 23 Feb 2024 10:09:12 -0500, "jason_warren@ieee.org"
<jason_warren@ieee.org> wrote:

>In article <2epeti1695iik2quktbascss2p7h3rdnjh@4ax.com>,
>memyself@null.net says...
>
>
>> Maybe your cable company sent a firmware update and blocked access? I know
>> I used to be able to log on to my cable modem to reset it but Spectrum now
>> blocks access on newer modems.
>
>Hmmm...I have Spectrum service. I'll ask.

It's kind of a pain in the ass that Spectrum does this. It was a Time
Warner tech that first showed me how to look at the modem's power levels and
things to see if there was a line problem and often resetting the modem
could fix it. This was back before they sold out to Charter/Spectrum. I
would purchase my own modem to save the monthly fee. Spectrum doesn't
charge a monthly fee for their modems but they block all access to them from
the user.

In article <6amhti1rfri6rnlahvpogm18d7cqcdf76b@4ax.com>,
memyself@null.net says...
>
> On Fri, 23 Feb 2024 10:09:12 -0500, "jason_warren@ieee.org"
> <jason_warren@ieee.org> wrote:
>
> >In article <2epeti1695iik2quktbascss2p7h3rdnjh@4ax.com>,
> >memyself@null.net says...
> >
> >
> >> Maybe your cable company sent a firmware update and blocked access? I know
> >> I used to be able to log on to my cable modem to reset it but Spectrum now
> >> blocks access on newer modems.
> >
> >Hmmm...I have Spectrum service. I'll ask.
>
> It's kind of a pain in the ass that Spectrum does this. It was a Time
> Warner tech that first showed me how to look at the modem's power levels and
> things to see if there was a line problem and often resetting the modem
> could fix it. This was back before they sold out to Charter/Spectrum. I
> would purchase my own modem to save the monthly fee. Spectrum doesn't
> charge a monthly fee for their modems but they block all access to them from
> the user.

Spectrum does charge $10/month for a combined modem/router. I
jumped off that bandwagon immediately! And I was able to log
on to the modem until recently, but I now believe that I have
a netmask issue - will connect laptop directly later today.

On Sat, 24 Feb 2024 12:35:28 -0500, "jason_warren@ieee.org"
<jason_warren@ieee.org> wrote:

>In article <6amhti1rfri6rnlahvpogm18d7cqcdf76b@4ax.com>,
>memyself@null.net says...
>>
>> On Fri, 23 Feb 2024 10:09:12 -0500, "jason_warren@ieee.org"
>> <jason_warren@ieee.org> wrote:
>>
>> >In article <2epeti1695iik2quktbascss2p7h3rdnjh@4ax.com>,
>> >memyself@null.net says...
>> >
>> >
>> >> Maybe your cable company sent a firmware update and blocked access? I know
>> >> I used to be able to log on to my cable modem to reset it but Spectrum now
>> >> blocks access on newer modems.
>> >
>> >Hmmm...I have Spectrum service. I'll ask.
>>
>> It's kind of a pain in the ass that Spectrum does this. It was a Time
>> Warner tech that first showed me how to look at the modem's power levels and
>> things to see if there was a line problem and often resetting the modem
>> could fix it. This was back before they sold out to Charter/Spectrum. I
>> would purchase my own modem to save the monthly fee. Spectrum doesn't
>> charge a monthly fee for their modems but they block all access to them from
>> the user.
>
>Spectrum does charge $10/month for a combined modem/router. I
>jumped off that bandwagon immediately! And I was able to log
>on to the modem until recently, but I now believe that I have
>a netmask issue - will connect laptop directly later today.

I'm not paying $10 a month for the modem/router. Time Warner used to. They
do charge $5 a month for wifi management which is why I just get a modem
from spectrum and use my own router.

[snip]

> I'm not paying $10 a month for the modem/router. Time Warner used to. They
> do charge $5 a month for wifi management which is why I just get a modem
> from spectrum and use my own router.

I would never use an ISP-provided ROUTER. They shouldn't have control
over MY network.

--
Mark Lloyd
http://notstupid.us/

"Atheist: A person who believes in one less god than you do." [Rev.
Donald Morgan, Atheologist]

jason_warren@ieee.org wrote:

[snip]

>
> The modem (Motorola DOCSIS 3.1) and the router (Linksys mesh). The modem
> is half a year old and the router s/w is up to date.
>
> Today's experiment is to connect my laptop directly to
> the modem. That's worked before.

Ah, some useful information at last.

So how is your laptop configured? First try "Auto" so it looks for a
DHCP server.

Disconnect your Motorola DOCSIS 3.1 from its fibre input.

Connect your laptop to the Motorola DOCSIS 3.1 and power up.

Does the laptop get an IP address?
Does the laptop get a default gateway address? (Possibly 192.168.100.1)
Can you ping the default gateway address?
Can you open a web browser at the default gateway address?

Disconnect the laptop
Now connect the fibre and wait until the relevant lights show that the
service is connected.
Re-connect the laptop.

Repeat the 4 tests above.

It is likely that when not connected to fibre, the modem issues an IP
address on its LAN, and you might be able to see its status page.

However, when connected to fibre, the DHCP server will stop, and the
laptop's DHCP requests will be sent to the ISP, so the laptop sees the
public IP address issued by the ISP. It will also get a different
default gateway. The laptop should be able to browse the web. Since
there is no firewall involved it will be susceptible to all the malware
out there. It won't be able to see the modem's status page because it
is now not on the same network.

It is possible that the modem will still respond on the default gateway
address you found in the first test. But to achieve this, your laptop
must be configured with a suitable static IP address and compatible
subnet mask. It should then see the modem's status page, but of course
it won't have any internet access.

If you interpose a network switch between the router and the modem, you
should be able to have a laptop connected to the modem as the same time
as the router.

--
Graham J

On Wed, 21 Feb 2024 19:35:02 -0500, Paul <nospam@needed.invalid> wrote:

>On 2/21/2024 4:36 PM, jason_warren@ieee.org wrote:
>> In article <MPG.40402d0456462ff89896ae@news.eternal-september.org>,
>> jason_warren@INVALID.ieee.org says...
>>>
>>> I've always been able to log in to my cable modem,
>>> a Motorola. Just now, I no longer can. Nothing's changed
>>> that I know of (famous last words...). I log in to look
>>> at the error rates to assure myself that the connection
>>> is not deteriorating. I also changed the default password.
>>>
>>> The modem's IP address is 192.168.100.1. Linking to that
>>> address times out. The net mask in the router is ff ff ff 00.
>>>
>>> Any ideas?
>>
>> PS - I tried all this on 3 different browsers on each of two computers
>> so I don't think browser security settings are the problem...
>>
>
>What is your PC IP address and netmask ?
>
>If I was on 192.168.1.2 and I tried to reach 192.168.100.1 ,
>that would not work,

Wait, that's wrong in this case.

Cable modem management IP addresses are kind of a unicorn. They live in RFC1918
address space, but they are technically WAN addresses, which might seem to be
contradictory but it's not.

With a router separating your LAN from the WAN:
If your LAN subnet is anything other than the subnet that contains the cable
modem IP address, then the cable modem address will appear to the router to be a
WAN address and will be treated as such. The router will pass it through from
the LAN side of the router to the WAN side of the router, where the cable modem
will see it.
Note: If your LAN subnet is the same as your cable modem address subnet, then
your cable modem will be unreachable in this scenario because the router will
consider it to be LAN traffic and will not pass the cable modem traffic through
to the WAN side. (Widening the netmask is an example of this and will ensure
that the cable modem will be unreachable.)

*Without* a router separating your LAN from the WAN:
This is, almost by definition, a direct connection from a single PC to the cable
modem, unless you have an agreement with your ISP (for an additional monthly
fee) allowing you to receive more than one IP address. The ISP will issue, via
DHCP, a routable address to the first device that's connected to the modem, and
it won't be in the same subnet as the modem's management IP subnet. However,
simply sending traffic to the address of the modem will result in the modem
responding because it sees all traffic passing through and recognizes that this
traffic is intended for itself.

Giant caveat: The ISP controls whether the cable modem will have a responsive
GUI. That is something they can enable/disable at will, via config files pushed
from their tftp server, which is part of their provisioning platform.

Rabbit hole time: Cable modems used to be easy to hack, allowing users to
reconfigure nearly everything, including the speed tier. These days, hacking is
a bit more difficult, but still possible. I don't recommend it. BTDT.

<snip>

On Thu, 22 Feb 2024 02:45:26 -0700, ...w¡ñ§±¤ñ <winstonmvp@gmail.com> wrote:

>Jason wrote on 2/21/24 1:54 PM:
>> I've always been able to log in to my cable modem,
>> a Motorola. Just now, I no longer can. Nothing's changed
>> that I know of (famous last words...). I log in to look
>> at the error rates to assure myself that the connection
>> is not deteriorating. I also changed the default password.
>>
>> The modem's IP address is 192.168.100.1. Linking to that
>> address times out. The net mask in the router is ff ff ff 00.
>>
>> Any ideas?
>>
>What 3 browsers did you try using?
>Your issue may be security related(SSL,TLS SMB)

I've never seen a cable modem that uses anything other than plain HTTP for its
management GUI. That applies to North America and South Korea. Perhaps I'm out
of touch.

On Thu, 22 Feb 2024 20:13:16 +0000, Graham J <nobody@nowhere.co.uk> wrote:

>GlowingBlueMist wrote:
>> On 2/21/2024 2:54 PM, Jason wrote:
>>> I've always been able to log in to my cable modem,
>>> a Motorola. Just now, I no longer can. Nothing's changed
>>> that I know of (famous last words...). I log in to look
>>> at the error rates to assure myself that the connection
>>> is not deteriorating. I also changed the default password.
>>>
>>> The modem's IP address is 192.168.100.1. Linking to that
>>> address times out. The net mask in the router is ff ff ff 00.
>>>
>>> Any ideas?
>>>
>> Try plugging a PC directly into the cable modem, verify you have
>> internet access, then try to log into the cable modem.  If it works then
>> I strongly suspect something in your router is blocking access to the
>> cable modem.
>>
>> If a direct Ethernet cable does not let you log into the modem then try
>> temporarily disabling all Firewalls and anti-virus software on the PC
>> and see if that works.  If it does then you are on your way to
>> identifying the culprit.
>
>Is this a combined router and cable modem? Or are there two separate
>devices?
>
>Disconnect modem from cable supplier.
>
>Apply factory reset. This should revert it to its original stage when
>you first got it.

That's generally not good advice because the cable modem would likely need to be
reprovisioned by the ISP before it would work again. That can take about 15
minutes to several hours, plus a phone call, depending on the ISP.

>Connect your PC using the Ethernet cable; you should get access.
>Continue to monitor the connection status so you can see if anything changes
>
>Then connect the modem to the cable supplier. After a minute or two you
>should get internet access - check using a different browser window.
>You might have to apply a username and password for the WAN connection -
>what did you do when this was first set up?

Cable modems don't have a username/password like some other devices do.

>You may find the status is no longer available. This might be because
>the ISP sees that your modem is out of date and sends the new firmware
>immediately. You might see it reboot a couple of times.

You're actually on to something. With a cable modem where the ISP has disabled
GUI access, you can power down the modem, disconnect the coax cable and power
back up. The management GUI should then be reachable, but of course it won't
have much useful information because the coax is disconnected. When you
reconnect the coax, the ISP will issue instructions via tftp to disable the GUI,
if that is their intent. In short, access to the management GUI is under their
control. Unless you go to the dark side, but we're not doing that here.