02/14/2012 4:13 AM
MTU configuration on IPStack
We have configured
MTU 1504 on en0 and
MTU 1500 on en1
But we have observed that during Ftp negotiations 1464 is advertised.
Incase MTU 1500 is configured both on en0 and en1, 1460 is advertised.
[Packet summary from wireshark]
13 14:35:28.886466 172.18.4.118 172.18.4.244 TCP cisco-ipsla > ftp [SYN] Seq=0 Win=65535 Len=0 MSS=1460
14 14:35:28.887697 172.18.4.244 172.18.4.118 TCP ftp > cisco-ipsla [SYN, ACK] Seq=0 Ack=1 Win=16384 Len=0 MSS=1464
where 172.18.4.244 is the IP for the site running on QNX
Pls. let us know what is the probable cause.