I have an issue where UDP packets are constantly being dropped through a 2811 router. When I do a show vlan 600 I get the following:
Vlan600 is up, line protocol is up
Hardware is EtherSVI, address is 0025.84fb.7590 (bia 0025.84fb.7590)
Description: Cisco Management Segment
Internet address is
MTU 1500 bytes, BW 100000 Kbit/sec, DLY 100 usec,
reliability 255/255, txload 1/255, rxload 2/255
Encapsulation ARPA, loopback not set
ARP type: ARPA, ARP Timeout 04:00:00
Last input 00:00:00, output never, output hang never
Last clearing of "show interface" counters 1w6d
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: fifo
Output queue: 0/40 (size/max)
30 second input rate 1037000 bits/sec, 176 packets/sec
30 second output rate 57000 bits/sec, 78 packets/sec
198077267 packets input, 2636187411 bytes, 0 no buffer
Received 12450725 broadcasts, 0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
88773918 packets output, 3948583617 bytes, 0 underruns
0 output errors, 0 interface resets
95053 unknown protocol drops
0 output buffer failures, 0 output buffers swapped out
The counter continually increases. I tried to setup a span session with the VLAN on the Router, but got the following:
(config)#monitor session 1 source vlan 600
SPAN Source Vlan is not supported in this platform
IOS: Version 12.4(15)T9
How can I find out why these packets are being dropped?
