Mini Protocol Analyzer (MPA)

Set up a packet capture on gi1/1 to caputre all packets tx/rx in a 10M circular buffer;

conf t
monitor session 1 type capture
source interface gi1/1 both
end
monitor capture dot1q circular buffer size 10000 start
%SPAN-5-PKTCAP_START: Packet capture session 1 started

See the captured packets (an ICMP ping in this example)

monitor capture stop
 %SPAN-5-PKTCAP_STOP: Packet capture session 1 ended at the user's request

show monitor capture buffer detail

125    Arrival time : 00:03:52.296 UTC Mon Jun 23 2014
        Packet Length : 114 , Capture Length : 68
        Src vlan : 2047 Ethernet II :  0001.4730.3c8e  0022.56ce.699c  0800
        IP: s=10.240.16.1 , d=10.240.16.5, len 100
        ICMP type=8, code=0
126    Arrival time : 00:03:52.300 UTC Mon Jun 23 2014
        Packet Length : 114 , Capture Length : 68
        Src vlan : 2047 Ethernet II :  0022.56ce.699c  0001.4730.3c8e  0800
        IP: s=10.240.16.5 , d=10.240.16.1, len 100
        ICMP type=0, code=0
conf t
monitor session 1 type capture
source interface gi2/8 both
buffer-size 1000
end
monitor capture length 1000 buffer size 1000 start for 60
monitor capture stop
show monitor capture buffer detail