Things I didn’t know about ESXi

I’m setting up a development server using vmware ESXi virtual server running CentOS 5.5 x64 and FreeBSD 8.0 x64. Currently, the second installation pass is in progress. Being fresh to ESX/ESXi there were couple of things I didn’t realize:

First (the reason for the reinstall), if there is plenty of hard drive space available, it’s good idea not to deplete it all for the sytem installations. I split a 1.3Tb RAID 5 array between the two operating systems until I realized that 1) you can’t shrink vmfs partitions and 2) by consuming all hard drive space one limits the flexibility of the system down the line. Let’s say you want to install a newer version of an operating system and decide to do a fresh install. You need space for it while you want to keep the old version around at least long enough to migrate settings and data over.

Second, while I was aware of that ESXi doesn’t offer console access beyond the “yellow and grey” terminal, I didn’t realize you have no access to the VM consoles, either. So, with CentOS or FreeBSD installed, the only way to access their consoles is via the vSphere client (someone correct me if I’m wrong — I wish I were as I’d like to have local console access to the guest OS’es).

Finally, VMware Go “doesn’t currently support ESXi servers with multiple datastores”. So if you have, say, a 3ware/LSI/AMCC RAID controller which isn’t currently supported under ESXi as a boot device but which you likely still want to use as a datastore, you’ll end up with at least two datastores. So vSphere is really the only way to go for VM management also for this reason (since LSI provides a vmware-specific driver, one may also be able to direct-connect the LSI RAID array to the VM without it being an ESXi datastore, but that’s not the configuration I’m looking for—the boot device is small and houses just ESXi while the VMs and their associated datastores are located on the array).

In the end everything’s working quite well. I like the flexibility virtualization offers.. and consolidation is useful even in a small environment (one dev machine is less than two or three dev machines :)).

One thought on “Things I didn’t know about ESXi”

  1. You are correct about your second point – there is no way to access the console other than through the vSphere client. I have been searching for a way of running Windows 7 and Linux simultaneously so that I can simply ‘tab’ between them. This is possible through the simplyinnovating SIOS on the BeagleBoard where simply pressing a physical button switches you between any of the running Android, Linux or ChromiumOS instantly whilst leaving the others running. The lack of any ability to access the clients on the machine running ESXi effectively removes any possibility of doing this. If you happen to know a way please do let me know.

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.