5-7
Catalyst 6000 Family Software Configuration Guide—Releases 6.3 and 6.4
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Chapter 5 Configuring Ethernet VLAN Trunks
Configuring a Trunk Link
Port Vlans allowed and active in management domain
-------- ---------------------------------------------------------------------
2/9 1,5,10-32,101-120,150,200,250,300,400,500,600,700,800,900,1000
Port Vlans in spanning tree forwarding state and not pruned
-------- ---------------------------------------------------------------------
2/9 5,10-32,101-120,150,200,250,300,400,500,600,700,800,900,1000
Console> (enable)
Configuring an ISL/802.1Q Negotiating Trunk Port
To configure a trunk port to negotiate the trunk encapsulation type (either ISL or 802.1Q), perform this
task in privileged mode:
This example shows how to configure a port to negotiate the encapsulation type and how to verify the
trunk configuration. This example assumes that the neighboring port is in
auto
mode with encapsulation
set to
isl
or
negotiate
.
Console> (enable)
set trunk 4/11 desirable negotiate
Port(s) 4/11 trunk mode set to desirable.
Port(s) 4/11 trunk type set to negotiate.
Console> (enable)
show trunk 4/11
Port Mode Encapsulation Status Native vlan
-------- ----------- ------------- ------------ -----------
4/11 desirable n-isl trunking 1
Port Vlans allowed on trunk
-------- ---------------------------------------------------------------------
4/11 1-1005,1025-4094
Port Vlans allowed and active in management domain
-------- ---------------------------------------------------------------------
4/11 1,5,10-32,55,101-120,998-1000
Port Vlans in spanning tree forwarding state and not pruned
-------- ---------------------------------------------------------------------
4/11 1,5,10-32,55,101-120,998-1000
Console> (enable)
Defining the Allowed VLANs on a Trunk
When you configure a trunk port, all VLANs are added to the allowed VLANs list for that trunk.
However, you can remove VLANs from the allowed list to prevent traffic for those VLANs from passing
over the trunk.
Task
Command
Step 1
Configure a port to negotiate the trunk
encapsulation type.
set trunk
mod/port
[
on
|
desirable
|
auto
|
nonegotiate
]
negotiate
Step 2
Verify the trunking configuration.
show trunk
[
mod/port
]
