Administrator Guide

VLANs 763
Assigning an 802.1p Priority to VLAN Traffic
The following example assigns all traffic on VLAN 25 to internal CoS
queue 4. This might be useful when assigning voice traffic a higher priority
than normal data traffic. Note that CoS queue 4 shares scheduling with the
other CoS queues, albeit more frequently than the lower-number CoS
queues.
To ensure that CoS queue 4 packets are always transmitted first, CoS queue 4
could be made a strict-priority queue. In this case, it would be prudent to rate
limit CoS queue 4 traffic.
1
Create an access list that permits all traffic and assign it to CoS queue 4.
console#config
console(config)#ip access-list voice-vlan
console(config-ip-acl)#permit every assign-queue 4
console(config-ip-acl)#exit
2 Assign the access list to VLAN 25. The access-group is given sequence
number 100.
console(config)#interface vlan 25
console(config-if-vlan25)#ip access-group voice-vlan in 100
console(config-if-vlan25)#exit
Configuring a Private VLAN
1 Configure the VLANs and their roles. This example configures VLAN 100
as the primary VLAN, secondary VLAN 101 as the community VLAN and
secondary VLANs 102 and 103 as the isolated VLANs:
switch#configure
switch(config)#vlan 100
switch(config-vlan-100)#private-vlan primary
switch(config-vlan-100)#exit
switch(config)#vlan 101
switch(config-vlan-101)#private-vlan community
switch(config-vlan-101)#exit
switch(config)#vlan 102
switch(config-vlan-102)#private-vlan isolated
NOTE: Spanning-tree status is shown accurately on the MLAG primary switch
and on the partner switches. On the MLAG secondary switch, interfaces may
show as spanning-tree disabled, but will remain in and are shown in the
forwarding state.