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New Member

VPN Communication Problem

I have created a working VPN between a remote PC with Cisco VPN Client and Easy VPN server on Cisco 1802 (DSL). The Router has an dynamic external IP and is accessible over DynDNS. The problem is not the VPN connetion, but the communication between the remote PC and LAN behind the router.

Ping functions to all devices on the LAN

telnet 25 functions

DNS functions

Access to shares is taking ages, functions then sometimes, usually runs it into a Timeout

HTTP is taking ages and breaks then

Remotedesktop to a 2k server breaks

Remotedesktop to a 2k3 server opens the server window, but before the login mask breaks

Application Security Log of the SDM:

JAN 16 14:09:35.902 PC Time DROP PKT Dropping tcp pkt =>

JAN 16 14:11:35.662 PC Time DROP PKT Dropping tcp pkt =>

Any idea's what's wrong with the config?


Re: VPN Communication Problem

Hi there,

I see some issues here:

1. Increase the value in the command:

ip tcp synwait-time 10

2. Remove following command from the interface Dialer0 config:

ip route-cache flow

3. On the VPN client PC, open the SetMTU utiliy (in the VPN client folder) and set the MTU on the interface to 1300.

Start the above steps and test after each.

Please rate if this helped.



New Member

Re: VPN Communication Problem

Thank's for help, the problem is solved. It was the VPN-Client version on the remote-PC.

I uninstall the Cisco VPN Client v4.7 and install v4.8. Now the VPN-communication is runnig great.