VMware Lab Manager, ssmove.exe and why I don’t care

Sounds like a depressing topic, but really it’s not all bad. As I’d mentioned previously, I’ve spent a good chunk of the previous 4 months commissioning a CLARiiON CX4-960 array and migrating data from our production CX3-40f and CX700. All told, there’s about 112TB in use, and I’ve moved about 90TB so far. I’ve had to use a number of different methods, including Incremental SAN Copy, sVMotion, vmkfstools, and, finally, ssmove. For those of you who pay attention to more knowledgeable people’s blogs, Scott Lowe had a succinct but useful summary of how to use the ssmove utility here. So I had to move what amounted to about 3TB of SATA-II configs in a Lab Manager 3.0.1 environment. You can read the VMware KB article for the instructions, but ultimately it’s a very simple process. Except when it doesn’t work. By doesn’t work I mean wait for 25 hours and see no progress doesn’t work. So I got to spend about 6 hours on the phone with the Live queue, and the SR took a long time to resolve. The utility really doesn’t provide a lot in terms of logging, nor does it provide a lot of information if it’s not working but has ultimately timed out. It’s always the last 400GB that we get stuck on with data migrations, isn’t it?

The solution involved manually migrating the vmdk files and then updating the database. There’s an internal-only KB article that refers to the process, but VMware don’t really want to tell you about it, because it’s a bit hairy. Hairier stil was the fact that we only had a block replica of the environment, and rolling back would have meant losing all the changes that I’d done over the weekend. The fortunate thing is that this particular version of ssmove does a copy, not a move, so we were able to cancel the failed ssmove process and still use the original, problematic configuration. If you find yourself needing to migrate LM datastores and ssmove isn’t working for you, let me know and I can send you the KB reference for the process to do it manually.

So to celebrate the end of my involvement in the project, I thought I’d draw a graph. Preston is a lot better at graphs than I am, but I thought this one summed up quite nicely my feelings about this project.