Hopefully the title of this discussion will give a bit of insight into my level of expertise....!....so please go easy on me if I have made any glaringly obvious and silly beginner mistakes! Anyway, my situation is this....
A few months ago I thought I might enter the virtual world, so I grabbed one of our old, decommissioned servers and set up ESXi 4 on it. As the server was an old one, it only had 2 x 74Gb discs on it, which were set up in a RAID array, making for 60-odd gig of disk space. I created my first virtual server, and gave it a thick-provisioned 30 Gb disc. I installed a web application, a network monitoring application and a SQL server application on it. It seemed to run quite well, and was serving it's purpose. We then had a need for another server for a new application we were installing, so I piped up and said to the boss that I could create a new virtual server for this new application (after all, I had set up 1 virtual server.....I was now an expert, right?!!), so I set up another virtual server on the same host. Once again I gave it a thick-provisioned 30 Gb drive. This left about 7 Gb free in the datastore, which I figured would be plenty as disc growth on both the virtual machines on this server was not expected to be very big (the first machine still had about 15Gb free, and when I set up the second virtual server it still had 20Gb free after installing the application it was created for).
Anyway, things were going along quite nicely.....both virtual servers were working nicely. Considering the fact that the host they were on was quite an old server, with only 4Gb of RAM, performance was more than adequate. Our only problem was that neither of these servers were being backed up, so I downloaded VEEAM Backup and Replication. I tried a backup of one of the virtual machines, but the backup failed. The error said there was not enough room in the datastore to take a snapshot. Since then I have had problems with the first of the 2 virtual servers occasionally locking up, and a message appears in the logs saying that 'there is no more space for virtual disk xxxxx. I may be able to free up more space on the partition.....'.. Both the virtual servers on this host still have many Gb free, so I am just wondering how I go about freeing some space on the partition, as the error message advises? Does this mean that my failed snapshot/backup has consumed the free space that I had previously had in my datastore? If so, how do I go about removing that? I have tried Googling how to do this, but the results seem to be rather cryptic and a bit confusing for this little black duck.
I do have some larger disks that I can add to this host, but unfortunately, seeing as how they are larger than the current discs I figure that I just can't pull one of the smaller discs, replace it with a larger disc, let the magic of RAID do it's thing, then pull the other smaller disc and and replace it with a larger disc. My beginner's brain tells me that I need to somehow back up both the virtual servers on this host, replace both discs and then just rebuild the host from scratch? I suppose I could migrate the virtual servers to another host (we now have ANOTHER host running 2 more virtual machines, that has a lot more disc space available), rebuild the original host, and then migrate them back to the original?
As I said at the beginning (and as will have become painfully obvious during the course of this post!!), I am a rank beginner......I just know enough to be dangerous......so any suggestions will be gratefully received.
