You know each packet entering the tunnel is encapsulated wtih gre key value. each packet exiting the tunnel is verified by the gre tunnel key value and de-encapsulated. the AS pic drops packets tht don't match the configured key value.
Since GRE doesn't provide encryption. This is like a simple clear-text password with no encryption. You can enable debug on Cisco box and see if you can catch the key; do the same thing on Juniper box (traceoption is your friend there) Regards, Masood -----Original Message----- From: juniper-nsp-boun...@puck.nether.net [mailto:juniper-nsp-boun...@puck.nether.net] On Behalf Of simon teh Sent: Saturday, July 11, 2009 10:55 AM To: juniper-nsp Subject: [j-nsp] Juniper (M20) - GRe Tunnel - Cisco(7206) Hi all, I have a question over here and have tried to find out the answer from the forum thread, but failed to get the answer. Did anyone experience this type of problem before: Juniper(M20) ----------------GRE tunnel-----------------------Cisco(7206) Juniper Configuration > show configuration interfaces gr-0/1/0 unit 0 { tunnel { source 219.93.2.1; destination 219.93.2.2; key 123456; } family inet { mtu 1514; address 192.168.1.1/30; } } Cisco Configuration interface Tunnel0 ip address 192.168.1.2 255.255.255.252 no ip unreachables no ip proxy-arp ip mtu 1514 tunnel source 219.93.2.2 tunnel destination 219.93.2.1 tunnel key 123456 The problem I had was if I configured both router WITHOUT the tunnel key, everything looks FINE. However once I include the tunnel key, then both tunnel UNABLE to ping (interface still up, up). Does anyone has any idea about the tunnel key between Juniper and Cisco. I am confident that other configuration is good, it is the problem with the key. Any suggestion? Thank you very much. _______________________________________________ juniper-nsp mailing list juniper-nsp@puck.nether.net https://puck.nether.net/mailman/listinfo/juniper-nsp _______________________________________________ juniper-nsp mailing list juniper-nsp@puck.nether.net https://puck.nether.net/mailman/listinfo/juniper-nsp