[X-Unix] How to determine which network component is failing

[Charles Howse]

On Jul 24, 2006, at 8:57 AM, Stroller wrote:

>
> Ummm... it would be. You need to grep it.
>

Yes, I understand, I've been curling/grepping the modem's signal data  
page to get the levels.
curl -s http://192.168.100.1/signaldata.html | grep dB | tr -d \<TD\>  
| tr -d /
returns:
37 dB
-5 dBmV
55 dBmV
where 37 is the s/n ratio, -5 is the downstream power level, and 55  
is the upstream power level.


>
> For my router:
>   $ curl -u admin:password http://pornpipe/doc/online.sht 2> /dev/ 
> null | grep -o '[[:digit:]]\{1,3\}[\.][[:digit:]]\{1,3\}[\.] 
> [[:digit:]]\{1,3\}[\.][[:digit:]]\{1,3\}'
>   192.168.1.43
>   212.104.130.9
>   192.168.1.1
>   82.153.1.4
>   213.152.39.89
>

That works for my router.  The ISP gateway ip is the 3rd line of 6.
[charles at larry:~]$ curl -u admin:pw http://192.168.100.254/ 
Status_Router.htm 2> /dev/null | grep -o '[[:digit:]]\{1,3\}[\.] 
[[:digit:]]\{1,3\}[\.][[:digit:]]\{1,3\}[\.][[:digit:]]\{1,3\}' |  
head -3 | tail -1
24.159.76.1
[charles at larry:~]$


> I might extract only the IP I'm interested in by heading & tailing  
> the output (for some reason that sounds so much nicer to me than  
> "by use of `head` and `tail`") but there are probably more elegant  
> ways of doing it - what happens if you're offline and the router's  
> webpage only shows the first 3 of those IPs? A good Bash script  
> will probably contain an "if $variable is NULL then" statement - I  
> can't remember off the top of my head how to do that but I know  
> it's described in the Advanced Bash Scripting Guide which is a free  
> download and always close at hand when I'm writing Bash scripts here.
>

On my router, I've only seen an ip of 0.0.0.0, the correct ip, and  
the old ip if the lease has expired.
So maybe I won't run into a null, but I'll script it anyway.  Good  
idea.  Got me a local copy of The ABSG!

>
>
>> I use static addresses on all the lan computers.  The dhcp server  
>> on the router is turned off.
>> One issue might be that the modem's lan address is 192.168.100.1,  
>> and the default address for the router is 192.168.1.1.  I have  
>> changed that to 192.168.254.254, and set the computers to  
>> 192.168.254.*/255.255.255.0.
>> Do you think it would help anything to set the router to  
>> 192.168.100.254, and the computers to 192.168.100.*/255.255.255.0?
>> Then everything would be on the same subnet.
>>
>
> Ummm... *rubs eyes*
> It's kinda early in the morning here, so please excuse me if I'm  
> reading that incorrectly... but the point of a router is that it  
> routes between two different subnets. Ummmm... if the modem has a  
> 192.168.x.y IP address then that suggests it's already doing some  
> NATting (certainly if the modem's external address is different).  
> If you put both interfaces of the router in the same subnet I don't  
> think it would work any more.
>

I've removed my original comments after receiving the bounce msg from  
the list server.
I must humbly correct myself.  When I set the routers address to  
192.168.100.254 and the computers to 192.168.100.*/255.255.255.0,  
everything worked, but I couldn't ping the modem nor see it's  
internal web page.
I've set everything back to the way I had it, and all is well.

> I haven't seen the source from the webpage that you use to reboot  
> the router, yet. Perhaps you could repost it, please? Since that'll  
> be plain-text html then an attachment would probably be quite  
> acceptable to the list. Use your web-browser to navigate to that  
> page and use "View > Source", but make sure you're not viewing just  
> the source to a frameset.
>

It's too big for the 5k limit.  It bounced.
I've posted it here:
http://bubbabbq.homeunix.net/router_status.html

> The "--form" parameter to `curl` may allow for button presses on a  
> webpage.
>

Hmmm...I'll have to play with that.
Thanks for all the info!  :-)



--
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