Dynamically Switching from a Primary MUF to a Shadow MUF

Products

• Datacom
• Datacom/AD
• Datacom/DB

Issue/Introduction

I have a question. We run in a Shadow MUF plex environment between 2 lpars. On LPAR1 we have our primary MUF and on LPAR2 we have the Shadow MUF.

When LPAR1 fails, the MUF automatically switches the Shadow MUF to a FULL MUF as it should. When LPAR1 is brought back it becomes a Shadow MUF.   

What we want to be able to do is to issue some type of operator command that will switch the primary back to LPAR1 without us having to stop the MUF on LPAR2. In other words, we're looking for the ability to dynamically switch back and forth between the Primary MUF and the Shadow MUF without taking either MUF down.

Environment

Release : 15.1

Component : Datacom/AD

Component : Datacom/DB

Resolution

The standard practice that many of our clients use when trying to switch back to the original or preferred configuration from having the primary MUF on LPAR2 and the Shadow MUF on LPAR1 is fairly simple. If you are using automated operations processing, you could issue an AO command, and this command would then give the primary MUF on LPAR2 the MUF EOJ command, causing the primary MUF(LPAR2) to end, and the Shadow MUF(LPAR1) to resume control as the primary MUF. The AO command would then wait until the MUF(LPAR2) is ended, and then it would restart it. This would cause the MUF(LPAR2) to start as the Shadow MUF, and it would be in a WAIT state as usual.

If I read your last sentence correctly, it sounds like you would want to do this: 

Switch the processing from MUF(LPAR1) to MUF(LPAR2) and let MUF(LPAR1) wait as the Shadow......ok, now switch the processing from MUF(LPAR2) to MUF(LPAR1) so the MUF(LPAR2) waits as Shadow...ok, now switch them again, &c. 

If so, this is not possible. The intention of the primary MUF / Shadow MUF process is that the primary MUF handles all the requests until an EOJ or a failure occurs, and then the Shadow MUF becomes primary. The original MUF is no longer running, and if it is started, becomes the Shadow MUF. There is no other way to demote a primary MUF to Shadow MUF status other than a shutdown or failure and a subsequent restart.

Additional Information

As always, please contact Broadcom support for Datacom if you have further questions.