VPN dropping out

[Guest]

We are having problems with our remote users VPN
connections dropping out. They are also sometimes unable to
access any resources on our network i.e network drives,
exchange server. When they are connected and occasionally
connect to exchange, outlook freezes and they have to
reboot their machines to get back on.
I have tried running RAS on a 2000 server machine and also
on a 2003 machine and we are getting the same problems. We
are using a watchguard firebox which i can't see is causing
a problem. Our remote users vpn to external address which
is mapped by the firebox to the ras server.
The 2000 RAS server has a bank of modems and a Gigabit
ethernet card. The 2003 server has 2 10/100 ethernet cards.
Any ideas what may be causing problems?

Craig

 

[Brian Higgins]

I've been troubleshooting a demand dial vpn connection issue at one of my
locations that's behind a T1.

4 branch offices can not maintain a vpn connection, or it drops out
frequently when it does establish one.

turns out we're seeing between 5% and 20% of all traffic across the wire is
TCP Retransmitions, and the problems with the VPN connections are directly
caused/related to the ammount of retransmissions we're seeing.

it's an ISP issue that we're still fighting... the ISP is about to get
replaced if they don't find this problem soon.

do some traffic analysis on your Wan circut and see what kind of errors
you're seeing and how many retransmits you're seeing.