We recently upgraded a Catalyst 6509 switch with a new Supervisor Module (WS-SUP2T-10G) running IOS vers. 12.2(50) SY3
After the upgrade we noticed an error using the WCCP protocol. The following log occurs everytime we enable the WCCP:
Nov 24 15:22:47.306: %TUN-4-MTUCONFIGEXCEEDSTRMTU_IPV4: Tunnel4 IPv4 MTU configured 17760 exceeds tunnel transport MTU 1476
Nov 24 15:22:47.306: %WCCP-5-SERVICEFOUND: Service 10 acquired on WCCP Client 10.176.16.240
This is the show tunnel inteface output:
Tunnel4 is up, line protocol is up
Hardware is Tunnel
Interface is unnumbered. Using address of Tunnel5 (172.16.0.1)
MTU 17864 bytes, BW 100 Kbit, DLY 50000 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation TUNNEL, loopback not set
Keepalive not set
Tunnel source 172.16.32.32
Tunnel protocol/transport multi-GRE/IP
Key disabled, sequencing disabled
Checksumming of packets disabled
Tunnel TTL 255, Fast tunneling enabled
Tunnel transport MTU 1472 bytes
Last input never, output never, output hang never
Last clearing of "show interface" counters never
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: fifo
Output queue: 0/0 (size/max)
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
0 packets input, 0 bytes, 0 no buffer
Received 0 broadcasts (0 IP multicasts)
0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort
0 packets output, 0 bytes, 0 underruns
0 output errors, 0 collisions, 0 interface resets
0 output buffer failures, 0 output buffers swapped out
This error is the cause of a buoncing behaviour on the internet connection using a Proxy configured with the WCCP and GRE protocol.
The tunnel interface is obviously not modifiable due to the fact that is created only when the WCCP is started so no modification can be made on the MTU size.
Can someone help me on this?
