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New Member

Strange connectivity problem

Hi all

This is a strange one.

I set up a site to site VPN 837>3005 concentrator wihout problems. The tunnel is up and running fine it seems, as i can always ping or telnet the remote (837) routers LAN ip, that should prove that the tunnel works.

Every X mins the connectivity stops, i.e unable to ping any host on the remote LAN (router LAN addr always OK to ping).

After 10 mins or so it starts working again by itself.

2 other ways is to ping 3005's WAN addr from remote LAN PC, or issue "clear arp" on the 837.

When it hangs the "show arp" shows arp table as it should.

Ping from 837 to any addr on LAN is still OK . I tried to lower the ARP timeout to 60 sec without fixing the problem.

Any brilliant ideas out there ?

New Member

Re: Strange connectivity problem

Try lowering the MTU to 1400 on the VPN link, also for trouble shooting purposes if your useing

3des, try regular des.

If it is a steady every 10 minutes, check your key lifetimes and make sure they don't expire every 10 minutes.

Hope that helps.

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