I have some trouble with some IP phone over a VPN site to site connection. It seems that the VPN tunnel can't stay up for a long time. Now it's up since 8 hours 34 minutes. But it will probably drop in a few hours.
This cause me some trouble with my IP phone. When the VPN drops, it reconnects after a few minutes. However, my phones don¿t come up. I need to power them off and restart them.
I don't know why my VPN tunnel drops.
For your information, the Adtran router is connected into a Sagecom 2864 Modem / router provided by BELL (ISP). The Sagecom is configured with a DMZ pointing to the Adtran router. It's designed like this because the Adtran box was not able to connect using PPPOE to the provider. We tried other router and it worked correctly. So we bypass this with a DMZ. And everything seems to work correctly.
I've attached the config files of both site.
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