There is a Cisco 2861 router (IOS version 12.4(3f)) serving as a VPN concentrator. Average number of simultaneously connected users rarely exceeds 200. But sometimes the router stops accepting any new connection. According to output from command 'show l2tun tunnel', the problem arises when there are more then 2000 L2TP tunnels. Most of them are idle tunnels to the same remote address. Here is an example in the file l2tun.txt. Is there any idle timer which could drop all those idle tunnels?