What is the role of MSM in Black diamond.

Userlevel 1
What is the role of MSM in Black diamond, can we use Black diamond without msm card. If I have to upgrade Black diamond do I have to upgrade each slot individually or upgrading msm upgrades all slots. Can I failover primary msm to secondary manually ? Do we have to select the other slot cards (non msm) based on Black diamond model / msm card installed ?

4 replies

Userlevel 5

The MSM is the Management module for the switch and acts as the master for the whole switch. You have to have at least one in the chassis at all times. If you have two they are active/active and provide additional slot bandwidth for the chassis. Additionally each of your blades has a packet processor so once the switch boots and the MSM's program them they can process packets and pass traffic without going through the MSM. As to upgrades, when you update the MSM it will ask you to update the firmware on the blades as well if it necessary.

Userlevel 1
Understood Bill I have read in some docs, if you have two msm, the one in the lowest port will be the master, and other will be standby. You say both msm will be active. What would be the correct answer ....... And also is manual failover of MSM possible, if yes what would be the command and in what circumstances we have to do a manual failover.......
Userlevel 7

MSMs in a BD8800 have 2 different roles:
- Management (1 is Master, 1 is Backup)
- Fabric (Forwarding of packets between modules)

So for Management, 1 is enough. For forwarding, you need both for full forwarding rate. With 1 MSM, you have half capacity. Please note that it's only for traffic ggoing from a Packet Processor to another (slot to slot or between ports on IO with multiple PP).
Userlevel 3
The command for a failover would be:
run msm-failover