Demote a MDC?

[dwstovall]

We have a single volume XSAN with two MDCs. We want to demote one of the MDCs because it is flaky and need to upgrade to XSAN 2.2, and the flaky MDC is not capable of being updated.

When I try to remove the machine from the XSAN, it pops and error saying that it can't write to one of the XSAN client machines. I don't understand why it would be trying to write something to one of the clients.

Regardless, it won't let me remove the flaky MDC. How can I demote it?

Thanks...

[wrstuden]

[dwstovall]

Where are the config files located on the client?

[wrstuden]

/Library/Filesystems/Xsan/config

The thing is that if you start manually editing the files, you can get your SAN config into an inconsistent state. Using Xsan Admin may have inconsistent results, and you may get odd errors.

I think you'll be best served by making Xsan Admin happy. Why can't it write to a client? Did you try removing the can't-write-to client from the SAN?

[jtownsend]

To add or remove a controller from your SAN, all clients must be online. That is the most likely reason this would fail.

[beskone]

indeed, make sure every client is online and accessible - then try to demote the MDC.

if you manually edit the config files, you'd better make sure they all match up or you can get really odd behavior from Xsan Admin.