VPN.BATTool to assist with diagnosing

VPN problems

Les Cottrell

Requires Perl

• Available at: http://www.activestate.com/

• download & install

Requires script

• copy vpn.bat to desktop from: groups on winsan1– v:\scs\networking\netdev\pl\vpn.bat

Execute

• Double click icon to run:

• Pops up DOS window which provides results of diagnosis:

Diagnosis 1 of 2• Checks version of Windows (W9x, WNT, W2K) and

service level etc.– Fail => Sorry I can’t help

• Checks whether user name is in SLAC domain– Warning => Need to specify SLAC\userid for VPN

• Tries/pings loopback Ethernet port

• Uses netstat -r to find gateway

• Pings gateway– Fail => No Internet connection

• Checks host registry to see if RAS installed, if not:– Fail => No RAS installed

Diagnosis, part 2 of 2• Pings well known host (ns1.slac.stanford.edu)

– Fail => Can’t ping ns1.slac.stanford.edu

• Does tracrt ns1.slac.stanford.edu, looks at output to see if first node in route is a VPN server– Fail => Can’t find VPN server in route

• Checks via nbstat -A to see whether there is an active VPN client– Fail => Looks like VPN server is not answering

Tested with:

• Windows 98, NT, 2000

• Ricochet

• DSL

Example of some of the output• You are running WinNT or 2K, major version 4, Service Pack 6,

minor version 0, build on atlas(134.79.118.3).

• OK, you are running Windows NT Service Pack 6, so I will try to help.

• vpn.bat checking if loopback is working on atlas...

• vpn.bat OK found loopback responds to ping on atlas

• vpn.bat looking for gateway using netstat -r ...

• vpn.bat OK found gateway 171.66.185.249 interface 171.66.185.251 metric 1

• vpn.bat checking if gateway 171.66.185.249 is reachable from atlas...

• vpn.bat OK gateway 171.66.185.249 responds to ping from atlas

• You appear to have RAS installed on atlas so I will continue checking...