Hi Ashish,
There are two reasons you would see a node unreachable
1. There is no path to the remote node
2. A network message sent to the remote node timed out after several retries
If you have a fairly large network with a very small stat reserve on your trunks, I would expect this to happen if there was some events that caused a lot of network messages to go out.
A node becoming unreachable does not necessarily mean that this node is not passing traffic.
It most likely did not respond to network messages because it was busy or the network messages sent to it were dropped in the path and hence did not reach the node for it to send a response.
In either case , stop all network affecting changes for some time and then try to add your trunk again.
Regards
Shajith
