[uropek]

На Cisco 3550 в выводе sh int много output buffer failures.

FastEthernet0/13 is up, line protocol is up (connected) 
 Hardware is Fast Ethernet, address is 0012.80bf.7b0d (bia 0012.80bf.7b0d)
 MTU 1500 bytes, BW 100000 Kbit, DLY 100 usec, 
    reliability 255/255, txload 102/255, rxload 2/255
 Encapsulation ARPA, loopback not set
 Keepalive set (10 sec)
 Full-duplex, 100Mb/s, media type is 10/100BaseTX
 input flow-control is off, output flow-control is unsupported 
 ARP type: ARPA, ARP Timeout 04:00:00
 Last input 00:00:00, output 00:00:00, 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 1128000 bits/sec, 1059 packets/sec
 5 minute output rate 40381000 bits/sec, 9379 packets/sec
    2609985344 packets input, 202031741 bytes, 0 no buffer
    Received 8967204 broadcasts (0 multicasts)
    0 runts, 0 giants, 0 throttles
    0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
    0 watchdog, 7406659 multicast, 0 pause input
    0 input packets with dribble condition detected
    1152740187 packets output, 4202459606 bytes, 662033352 underruns
    0 output errors, 0 collisions, 1 interface resets
    0 babbles, 0 late collision, 0 deferred
    0 lost carrier, 0 no carrier, 0 PAUSE output
    662033352 output buffer failures, 0 output buffers swapped out

Вы выводе show buffers:

CPU4 buffers, 1524 bytes (total 450, permanent 450):
    224 in free list (0 min, 450 max allowed)
    28761820 hits, 0 misses
CPU2 buffers, 1524 bytes (total 10, permanent 10):
    1 in free list (0 min, 10 max allowed)
    30597020 hits, 5360017 fallbacks
CPU6 buffers, 1524 bytes (total 10, permanent 10):
    1 in free list (0 min, 10 max allowed)
    12263726 hits, 1231114 fallbacks
CPU12 buffers, 1524 bytes (total 20, permanent 20):
    10 in free list (0 min, 20 max allowed)
    10 hits, 0 misses
CPU13 buffers, 1524 bytes (total 32, permanent 32):
    1 in free list (0 min, 32 max allowed)
    102 hits, 3 fallbacks

Нагрузка на порт даже к 50Мбит не поднимается. Пора срочно на гигабит или еще на сотке?