user manual

16-10
Catalyst 3750 Switch Software Configuration Guide
OL-8550-09
Chapter 16 Configuring Private VLANs
Configuring Private VLANs
• A private-VLAN host or promiscuous port cannot be a SPAN destination port. If you configure a
SPAN destination port as a private-VLAN port, the port becomes inactive.
• If you configure a static MAC address on a promiscuous port in the primary VLAN, you must add
the same static address to all associated secondary VLANs. If you configure a static MAC address
on a host port in a secondary VLAN, you must add the same static MAC address to the associated
primary VLAN. When you delete a static MAC address from a private-VLAN port, you must remove
all instances of the configured MAC address from the private VLAN.
Note Dynamic MAC addresses learned in one VLAN of a private VLAN are replicated in the
associated VLANs. For example, a MAC address learned in a secondary VLAN is replicated
in the primary VLAN. When the original dynamic MAC address is deleted or aged out, the
replicated addresses are removed from the MAC address table.
• Configure Layer 3 VLAN interfaces only for primary VLANs.
Configuring and Associating VLANs in a Private VLAN
Beginning in privileged EXEC mode, follow these steps to configure a private VLAN:
Note The private-vlan commands do not take effect until you exit VLAN configuration mode.
Command Purpose
Step 1
configure terminal Enter global configuration mode.
Step 2
vtp mode transparent Set VTP mode to transparent (disable VTP).
Step 3
vlan vlan-id Enter VLAN configuration mode and designate or create a VLAN that
will be the primary VLAN. The VLAN ID range is 2 to 1001 and 1006
to 4094.
Step 4
private-vlan primary Designate the VLAN as the primary VLAN.
Step 5
exit Return to global configuration mode.
Step 6
vlan vlan-id (Optional) Enter VLAN configuration mode and designate or create a
VLAN that will be an isolated VLAN. The VLAN ID range is 2 to 1001
and 1006 to 4094.
Step 7
private-vlan isolated Designate the VLAN as an isolated VLAN.
Step 8
exit Return to global configuration mode.
Step 9
vlan vlan-id (Optional) Enter VLAN configuration mode and designate or create a
VLAN that will be a community VLAN. The VLAN ID range is 2 to
1001 and 1006 to 4094.
Step 10
private-vlan community Designate the VLAN as a community VLAN.
Step 11
exit Return to global configuration mode.
Step 12
vlan vlan-id Enter VLAN configuration mode for the primary VLAN designated in
Step 2.
Step 13
private-vlan association [add | remove]
secondary_vlan_list
Associate the secondary VLANs with the primary VLAN.