VLAN problems

[Alexandre Biancalana]

On 1/29/08, Tom Judge <tom at tomjudge.com> wrote:
> Alexandre Biancalana wrote:
> > Hi Tom ! Thanks for your help!
> >
> > I had to step back the chance an put the "old" gateway back, the
> > performance was unacceptable  :-(
>
> Where these 2 systems connected to the same switch port and cabling?
> Could you post the interface error counters from the switch port?

All the external links are connected to a 2950.

The new gateway have only one gigabit ethernet interface connected to
our 4506 core switch, that is parent of all vlans, in this case all
the internal networks and external links are vlans.

The parent interface of the vlans in the old gateway is connected to
the same 2950.

#sh interfaces fastEthernet 0/11
FastEthernet0/11 is up, line protocol is up (connected)
  Hardware is Fast Ethernet, address is 000b.be44.3ccb (bia 000b.be44.3ccb)
  MTU 1500 bytes, BW 100000 Kbit, DLY 100 usec,
     reliability 255/255, txload 10/255, rxload 5/255
  Encapsulation ARPA, loopback not set
  Keepalive set (10 sec)
  Full-duplex, 100Mb/s, media type is 100BaseTX
  input flow-control is unsupported output flow-control is unsupported
  ARP type: ARPA, ARP Timeout 04:00:00
  Last input never, 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: 0/40 (size/max)
  5 minute input rate 2032000 bits/sec, 865 packets/sec
  5 minute output rate 4296000 bits/sec, 911 packets/sec
     608489542 packets input, 3377246124 bytes, 0 no buffer
     Received 5492 broadcasts (0 multicast)
     0 runts, 0 giants, 0 throttles
     3 input errors, 3 CRC, 0 frame, 0 overrun, 0 ignored
     0 watchdog, 0 multicast, 0 pause input
     0 input packets with dribble condition detected
     595743491 packets output, 2124861910 bytes, 0 underruns
     0 output errors, 0 collisions, 2 interface resets
     0 babbles, 0 late collision, 0 deferred
     0 lost carrier, 0 no carrier, 0 PAUSE output
     0 output buffer failures, 0 output buffers swapped out


>
> This error is because 1473 bytes as a pay load makes your icmp packet
> 1501 bytes long and you have set the do not fragment bit in the IP
> header so with an interface mtu of 1500 bytes this will not work.

Right, I'm just guessing.... because I don't understand why I start to
lost packets when I enable all networks as vlans....