Re: Vlan Interface drops

It a 3550 running IOS 12.1(11)EA1.

I used the term QOS a bit loosely. There is no service-policy on the
VLAN Interface. Although this interface is routing a high volume (8Mb
or more) of Multicast Video, and SNMP traffic. And yes, I checked and
CEF is running on that interface.

Thanks,
Jeff

Charlie Root wrote:
<sieber@xxxxxxxxxxx> wrote in message
news:1140653124.035939.190820@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
I need an explination of the Show Interface Vlan command if anyone can
help me with this.

I am troubleshooting QOS issues on a switched network, and have found
both output and input drops on vlan interfaces. Since a vlan
interface is has no physical port associated with it, I am having a
hard time understanding why the packets would be dropped. I am not
seeing drops at any of the physical interfaces between the hosts in
question, only at the vlan interface. The hosts are obviously on
different subnets, and are routed via this vlan interface.

You're saying that this is related to QoS. Did you attach a 'service-policy'
to this VLAN interface then? If yes, using 'show policy interface Vlan<N>
output|input' will tell you wether packets are dropped due to policy.

Another reason for packet drops on the input could be due to process
switching of high volume traffic. Check if CEF is running on that interface.

Kind regards,
iLya

.

Relevant Pages

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