Spanning-Tree between HP Comware and Cisco

In the past, I had many problems with a heterogene infrastructure containing HPE 5000 Comware devices and Cisco Catalyst switches. I couldn’t get Multiple Spanning-Tree (MSTP) on the run (same revision number, same case-sensitive region-name). So we decided to go on with Per VLAN Rapid Spanning-Tree. But this also didn’t work, also no other VLANs that VLAN 1 could be transported, Cisco runs into PVST simulation with correct MSTP configuration (Messages like “Bound(PVST)” and “*PVST_Inc” in show spanning-tree output), etc. After several attempts we got a final configuration.

Cisco and HP have also different STP path-costs -.-

Our next problem was, that two connected Cisco Switches auto-negotiat their interconnects as trunk-ports (VLAN 2-4094 tagged). In case that we migrate to our new 5700 HPE comware switch, we needed also to configure each uplink port like this:

interface GigabitEthernet0/1
switchport trunk encapsulation dot1q
switchport mode trunk

we consistent configured this stp configuration on the cisco switches:

spanning-tree mode rapid-pvst
spanning-tree extend system-id

keeping in mind, that we need the same path-cost at Cisco and HP switches, this was our final HP configuration (this switch was also the root-bridge):

stp vlan 1-4094 priority 0
stp mode pvst
stp pathcost-standard dot1d-1998
stp global enable

So “dot1d-1998” brings the path-cost-calculation to the Cisco level 🙂 I hope that I can help some people. Didn’t find any direct solution to my problem online about this.

1 thought on “Spanning-Tree between HP Comware and Cisco

  1. Hi, thank you very much for this post, you saved my life during a Core Switch migration from Cisco to HP Comware (with Cisco Access Switch all around).

    Hold on!

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