I faced with this strange situation also.I have dozen WS-C3850-48P with IOS Version 16.3.7 connected to central WS-C4507R+E.I have a lot of MACs like 0000.00ff.* on the central switch and nowhere else.I guess it may be connected with RSPAN, configure...
Hello,I would suggest to set MTU on tunnel interface to 1500 ("ip mtu 1500") without "tunnel path-mtu-discovery".This should prevent dropping large packets with DF-bit, which enters to GRE tunnel.Fragmentation will be occur of course, but it less evi...
I think we are complicating a problem with packet capture :-).What about ASA logs? Deletion of a TCP connection should go along with "Teardown" message. So "Teardown" log entry contains a reason.There are list of them http://www.cisco.com/en/US/docs/...
If you want to prove that firewall stops a TCP session (not server) i suggest you start packet capture between host and server on both interfaces of ASA, which traffic crosses.So, compare two captures of the TCP session you can see, who indeed send R...
If you have another cisco router on site, you can use it's AUX-port and rollover cable to connect to console of the new router.It needs configuration for AUX-port (line aux 0).This method is described there http://www.ciscozine.com/access-to-the-con...
