A networking problem

Fri Apr 27 08:15:28 PDT 2012

On 04/27/2012 10:03 AM, Stuart Biggerstaff wrote:
> If you connect directly to the modem, does the PC have to have the information for the ISP connection, or does that still live on the modem, and does the attached PC get a private IP from the modem?  Cisco has some specific instructions (implying non-default router behavior) for cascading a Linksys router with another router--which is what the modem is if it isn't giving attached devices an Internet IP.
> http://www6.nohold.net/Cisco2/ukp.aspx?pid=80&vw=1&articleid=3733

Stuart, thanks for the link.

When I connect either the router or my PC directly to the modem, no 
information from the ISP has to provide to make it connect to the 
Internet. The modem gives the router/PC a live IP address.

An administrator from the clients told me he has very similar problem 
with mine, and that problem rises because of the mismatch of duplex 
and/or speed negotiations between the modem and the router. His router 
is a high-end router so he can see those warnings from the log to fix 
it. I am going to put a switch between my router and the modem and see 
what happens.

Thanks,
Vu

>
>
> Stuart Biggerstaff
>
> -----Original Message-----
> From: linux-users-bounces+biggers=lindahall.org at linux-sxs.org [mailto:linux-users-bounces+biggers=lindahall.org at linux-sxs.org] On Behalf Of Vu Pham
> Sent: Friday, April 27, 2012 9:15 AM
> To: linux-users at linux-sxs.org
> Subject: Re: A networking problem
>
> On 04/26/2012 07:46 PM, Raymond Russell wrote:
>> One of our remote office is serviced by cable and a VPN box.  The Cisco VPN would not work with the cable company modem.  The cable company seemed to be aware of the problem and replaced the modem with a different brand and the connection worked right away.  Maybe the modem just does like Cisco/Linksys products.
>
> Some google results show one admin has a similar problems. He replaces
> that modem with a newer model and that fixes it. I will try some other
> options before either getting another brand of router or a newer model
> of modem.
>
> Thanks,
> Vu
>
>
>
>>
>>
>>
>> On Apr 26, 2012, at 6:15 PM, Lonni J Friedman wrote:
>>
>>> Have you verified that the cable modem has the newest firmware?
>>>
>>> On Thu, Apr 26, 2012 at 2:28 PM, Vu Pham<vu at sivell.com>   wrote:
>>>> On 04/26/2012 01:47 PM, Sean Keating wrote:
>>>>> So you have to ask what is the difference between the routers and the
>>>>> linux box. Are you testing with the same cables in all situations? Are
>>>>> the routers doing any firewalling or packet filtering? Can you get your
>>>>> hands on another brand of router to see if there is a difference?
>>>>>
>>>>
>>>> Sean,
>>>>
>>>> Turning on/off the router firewall does not help.
>>>>
>>>> Using another brand of router will be my last choice because I have a
>>>> bunch of routers here. Unfortuantely they are all Linksys/Cisco. I may
>>>> have to try a real Cisco router instead of the "home" version.
>>>>
>>>>
>>>> Thanks,
>>>>
>>>> Vu
>>>>
>>>>
>>>>> On Thu, 2012-04-26 at 07:11 -0500, Vu Pham wrote:
>>>>>> I need your advice !!!
>>>>>>
>>>>>> Recently my home network is pretty slow when accessing the Internet .
>>>>>> Contacting the ISP's support shows the problem is my Linksys (E3000)
>>>>>> router. Their tests are:
>>>>>> - connecting the PCs directly to the ISP cable modem ( a Motorola )
>>>>>> shows the bandwidth as high as expected.
>>>>>> - connecting the PCs to my router, which connects to the modem, shows
>>>>>> the bandwidth is pretty low.
>>>>>>
>>>>>> So I got another router (E4200) to test but it shows the same pattern:
>>>>>> slow with router, fast with modem only.
>>>>>>
>>>>>> I do not believe that both routers are bad so I install a Linux server
>>>>>> that acts as a router between the Linksys router and the modem. The
>>>>>> purpose is to check the packets and bandwidth from the router.
>>>>>>
>>>>>> Well, now all my PCs (wireless or wired) behind the Linksys router
>>>>>> access the Internet as fast as when I connect them directly to the modem.
>>>>>>
>>>>>> How can this be ? Some kind of conflicting between the Linksys routers
>>>>>> and the modem ?
>>>>>>
>>>>>>
>>>>>> Thanks,
>>>>>> Vu
>>>>>> _______________________________________________
>>>>>> Linux-users mailing list
>>>>>> Linux-users at linux-sxs.org
>>>>>> http://mailman.celestial.com/mailman/listinfo/linux-users
>>>>>
>>>>>
>>>>
>>>> _______________________________________________
>>>> Linux-users mailing list
>>>> Linux-users at linux-sxs.org
>>>> http://mailman.celestial.com/mailman/listinfo/linux-users
>>>
>>>
>>>
>>> --
>>> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>>> L. Friedman                                    netllama at gmail.com
>>> LlamaLand                       https://netllama.linux-sxs.org
>>> _______________________________________________
>>> Linux-users mailing list
>>> Linux-users at linux-sxs.org
>>> http://mailman.celestial.com/mailman/listinfo/linux-users
>>
>> _______________________________________________
>> Linux-users mailing list
>> Linux-users at linux-sxs.org
>> http://mailman.celestial.com/mailman/listinfo/linux-users
> _______________________________________________
> Linux-users mailing list
> Linux-users at linux-sxs.org
> http://mailman.celestial.com/mailman/listinfo/linux-users