Really. Please read the contact page and then the "Reporting Problems" section and be a lot more verbose. Note also that you have a heartbeat tunnel, but you mention "a cisco". As such, are you running a heartbeat client? A tunnel which is not up, is not configured and thus indeed you will get a !N from the PoP.

The state of this ticket has been changed to user

Let's describe my setup in more detail: PC 1 \ PC 2 ------ Cisco Router (NAT) ---- Inet PC 3 / \ PC 4 PC 1 running AICCU (version from 2007.01.15), installed using Gento Portage. The Cisco router has IPv6 over IPv4 tunnel configured as described in the FAQ but using it's dialer interface as local endpoint (I have dynamic IPv4 address and can't use static tunnels for this reason) I'm using my tunnel T12142, heartbeat being sent from PC1 heartbeat message looks like: HEARTBEAT TUNNEL <tunnel endpoint> sender <timestamp> <hash> My clock is synchronized against ntp server (pool.ntp.org) PC 1 can send icmpv6 echo requests to computers on the internet (eg PC 4) but the reply never reaches the cisco router (incoming packet count remains zero, outgoing packet count increases) tcpdump on PC 4 sees the incoming echo requests and also the outgoing echo replies but nothing arrives on cisco router. My setup has not changed at all between yesterday evening (working) and today (not working anymore). I usually shutdown my complete LAN on evening to save power over night and on the following morning it comes up without any issue. Only explanation I would have is some change on the broker side. If the heartbeat was not seen be the broker (nlams4) the echo requests should never reach the internet... Tunnel information page shows some obsolete IP address for my endpoint. From PC 4 the broker endpoint of my tunnel is not reachable (ping), aiccu test from PC 1 fails on ping to broker endpoint of my tunnel.