Core switchs: G1,G2,C1,C2,A1 = HP Procurve 5406lz (Firmware 16.02) Distribution switchs: GD1,CD1 = HP Procurve 2810-48G
In this post i’ll describe how to configure all switchs to build a network like in the picture. Between the 3 buildings, we have should have a theorical 40GB/s backbone.
This setup involve LACP and Distributed Trunk LACP and no spanning-tree
DT-LACP provide the possibility to link a single switch to two core switch without spanning-tree.
Before going further, check if all your switches have the same version of the firmware. Otherwise, your setup will be unstable (high cpu usage in my case)
Between G1 and G2 we configure a ISC (Inter Switch Connection) in LACP, the ISC have a Keepalive link, this can be a simple copper cable 100M, the keepalive is only used to monitor the ISC, btw the ISC can work without this cable. Same setup between C1 and C2.
Except the ISC all other trunks are configured as a DT-LACP (Distributed Trunk Link Aggregation Control Protocol).
Core switchs are slow
Check if the core switch cpu usage is not too high
Mine is ~1%, if your usage is too high (>50%), you miss something or LACP is in sync, check if spanning tree doesn’t block anything if it’s activated and check your lacp / dt-lacp status. I had the issue after a reboot test of the setup, after some ping, cpu usage came back to a normal state.