I have two routers with an OpenVPN link between them (home & office). For the past couple weeks I've been trying to trace down a bug where the link keeps getting re-established every 10 minutes. On the server side I had OpenVPN running on both a linux box and on a WNR3500L w/tomato. Both logs showed the same thing... Every 10 minutes the client would reconnect (but the old link never was disconnected). Ruling out any issues on the server side I started looking at the client side. The client was a WRT54GS running DD-WRT. At first I read someone with a similar issue regenerated their certs/keys and that solved their problem. I did that and nothing changed... So then I flashed a different build of DD-WRT claimed to be a good stable build... Still had the same issues. At home we have AT&T U-Verse with their crappy 2wire router that has so few user-configurable features that it's a wonder the thing works at all. Anyhow, digging through the few pages there are I saw that UDP timout was set at 600 seconds (10 minutes). AH HA! (So I thought)... I changed the time to the max allowed. However, the issue persisted every 10 minutes! WTF? Finally I thought to myself. Since I had my WRT set as the DMZ device (a change I only made recently), perhaps that was the issue? So I changed the UDP session timeout back, un-set my WRT as the DMZ... Guess what? The session issues with OpenVPN went away and now log notices are back to minimal things... I swear the 2wire products will be the end of me... I can't believe AT&T insists on using those pieces of junk. This is just some friendly information in case there is someone else out on the internet with the exact same problem as me.