I want to build a new 'core' for our network. We currently have a 3com 4060 switch acting as the core, connecting all the other TOR and access switches together.
The goal is to add resilience into the core, without compromising performance.
Each switch currently connects to the core with between 2 and 4 physical links configured as LACP trunks.
I am looking at replacing the 3com with a pair of HP 2920 switches with the optional stacking module. My understanding is that with the stacking module, the 2 switches will act as 1 'virtual' switch so I can connect each link from the access switches to each 2920:
The actual question
I know this isn't an unusual arrangement, but my questions are:
- Can it be done with the HP 2920 switches?
- Should I be using the HP "Trunk" type of trunk instead of LACP?
I've found a lot of conflicting information. A lot of sources say that either Distributed Trunks can only be done with 3xxx or higher switches but the HP QuickSpecs say that DT is possible with the 2920. Other sources say that DT can only be done between a pair of switches and a server (not other switches) but if the DT appears as a LACP trunk to the 'downstream' device then how does it matter?
I could do this using STP to block the links between the access switches and the second core switch, but I don't want to waste all that bandwidth.