I run a small Windows 2003 network with Active Directory. For remote access, I use an Astaro firewall/VPN that authenticates to my domain controller using Microsoft IAS. Users access it through Remote Desktop COnnection.
The VPN connection seems to be working. However, strange problems sometimes crop up. For example, one night I cannot map network drives, or I get a "Cannot Logon" message. I used to not be able to ping computers by name although this seems to work now. Finally, some users have told me that after 20-30 minutes, the connection seems to freeze and they have to login again.
My question is how to go about troubleshooting these problems. I have turned on IAS's logging and use IASPARSE to read the logs, but I need more information. I also use the Event logs when possible. Is there a general troubleshooting or tool out there that would be helpful? A book? For example, for network connectivity problems, I would advise people to do an IPCONFIG, followed by a series of PINGS, followed by TRACERT. Is there something similar for VPNs?
In a simialr vein, how can I test the security of my VPN? Any tools/references/websites recommended?