DNS problem with SSL VPN in tunnel mode

[horinius]

Since we have SSL VPN (in tunnel mode) set up in our FGT80C (version 4.1.4) on June 2010 by our vendor, we' ve been noticing a strange DNS problem. No, it' s not about the DNS suffix problem, but a real DNS problem. We noticed that sometimes host names are not resolved at all, eg ping 1.2.3.4 has replies while ping name.mydomain.com has no reply and this is the case whatever name is used. I was pretty sure DNS request didn' t get to our internal DNS server but it is totally reachable because ping dns_ip_address has replies But I don' t know how to " follow" DNS requests to see where they are actually sent to, so I can' t confirm on this point. What' s annoying with this problem is that it' s not reproducible. At least, I' m unable to find the pattern how to reproduce it at ease. But I have a little trail (or maybe just some unfortunate co-incidence?): when I reboot the FGT and I immediately connect to VPN, 4 out of 5 times I come across this problem. But if I use another computer to connect another VPN (the first VPN tunnel is still maintained), the 2nd computer has no DNS problem. So all I can do to my end-users is to tell them to reconnect VPN again and again until that works... :( Has anyone come across this problem? Known bug? Or bad config?

[atong888999]

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