877 Internet Access problem

Unanswered Question
Dec 24th, 2008
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HI All,

having a stange problem here..

i had a 2611 with 2 ethernet ports one for LAN and the other terminating on the ISP Internet device (radio bridge)

it worked well i has setup a tunnel to the head office and PATTED for internet acess

now we bought a 877 to replace that and made vlan1 as LAN and vlan2 as Internet

i can access the head office via tunnel 1 but the PATTING doenst seem to work any more...

from my desktop ic an ping google.com and other public ip add /names but cant seem to open any page or browse the internet

intranet pages from head office servers work fine..

is this a problem with 877 ???

what am i doing wrong ? plz help ..


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Richard Burts Wed, 12/24/2008 - 06:13
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Your post suggests that it is a problem with PAT. But it also says that you can ping public addresses in the Internet. If the problem were PAT then I would expect ping to not work. And if ping does work then it suggests that the problem is not with PAT but is with something else.

I notice that on the tunnel interface you have configured this:

ip tcp adjust-mss 1400

but on VLAN 1 and 2 you have configured:

ip tcp adjust-mss 1452

I am not sure why you have done this inconsistently. I would suggest that you make the value on VLAN 1 and 2 lower and see if it helps with your problem.



zaidumer Wed, 12/24/2008 - 07:14
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i did that but no difference

it even shows the ips being natted but nothing shows up

i have an 877 with adv sec IOS can it be an IOS bug ??

cause i have the same configuration working on 2611.. been pulling my hairs for the whole day now..

Pro Inside global Inside local Outside local Outside global

tcp 124.29.xx.xx:1354

tcp 124.29.xx.xx:1356

i really need this to work .. was suppose to be a simple 123 task :-(

zaidumer Thu, 12/25/2008 - 04:29
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any help ????

cant get browsing to work via PAT

zaidumer Fri, 12/26/2008 - 04:40
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no , am not.

just picked up a hint that maybe my IOS doesnt support multiple vlan routing

im using (C870-ADVSECURITYK9-M), Version 12.4(9)T7

somone suggested tat i upload an advance ip service IOS

lets hope that works.


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