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vlan information across trunk

Occasional Advisor

vlan information across trunk

I need to connect 2 ports on switch to 2 ports on another switch for aggregate bandwidth and fault tolerance. There are 4 vlans that span these switches. What is the best way to send VLAN information across this trunk. I think I remember reading back in the day that LACP doesn't pass VLAN information.

Thanks for any help
Mohieddin Kharnoub
Honored Contributor

Re: vlan information across trunk


The best way if you have ProCurve switches, is to make a trunk fro mthese 2 links, then pass all the Vlans required on this trunk by tagging.

Just keep everything to its default, and you will get what do you need.

Good Luck !!!
Science for Everyone
Trusted Contributor

Re: vlan information across trunk

To have two or more individual links behave like one logical link (for more bandwidth and redundancy), it is recommended to use LACP (link aggregation control protocol), described in IEEE 802.3ad standard. For ProCurves youl will need to include both ports at both ends in a trunk.

To carry multiple VLANs over any type of link between switches (aggregated or not), it is recommended to use the VLAN tagging, described in IEEE 802.1q standard. Frames in one VLAN may be passed untagged over the link, but frames from all other VLANs must be tagged. When you define VLANs on the switches, the names and 802.1q VLAN IDs must match.
Matt Hobbs
Honored Contributor

Re: vlan information across trunk

If you want VLAN information to be passed automatically you can use GVRP. Check the advanced traffic management guide for more information on this feature.

"GVRP enables the switch to dynamically create 802.1Q-compliant VLANs on links with other devices running GVRP. This enables the switch to automatically create VLAN links between GVRP-aware devices. (A GVRP link can
include intermediate devices that are not GVRP-aware.) This operation reduces the chances for errors in VLAN configuration by automatically providing VLAN ID (VID) consistency across the network."

Like the other suggestions, I prefer to create and tag them manually.