VMware RedHat guest

prowla · 02-08-2011, 03:47 AM

Hi.

We are building RedHat Linux 5.4 64-bit VMs on VMware, and it has been suggested that the primary swap should be on a disk partition (sda2), rather than on LVM.

It would be great to get comments & thoughts on this.

FYI, the role of the machines is app/web servers, and they may have 2 or 4 virtual CPUs and 4, 8, or 12 GB memory. The other filesystems are /boot (sda1), / (LVM on sda), /app (LVM on sdb), and the machines have VMware Tools installed.

Thanks very much!

phil.d.g · 02-08-2011, 04:06 AM

LVM would add a small overhead as it maps virtual blocks to the real blocks on the drive. Aside from that, and the overhead is marginal I can't see why you would go out of your way to put swap on a real partition. By default the Redhat installer will create a real partition for /boot and LVM volumes for swap and root.

prodev05 · 02-08-2011, 04:14 AM

Is the machine is a Server hardware or Hypervisor?

prowla · 02-08-2011, 04:52 AM

phil.d.g:
Yes, you have summarised my thoughts on the matter.

prodev05:
Our environment is ESX, and the server that the VM is currently resident on is a Proliant BL685c G1 blade with 4x dual-core 2.8 GHz CPUs and 64 GB memory, running vSphere 4 Enterprise. Our environment consists of something like 18 blades running a selection of Linux and Windows VMs. The storage is implemented on SAN-attached EVA disk arrays.

prodev05 · 02-08-2011, 07:08 AM

Then what phil.d.g mentioned is correct.

I too suggest the same. But don't go for auto layout on file system, pl do manual layout.

prowla · 02-08-2011, 08:38 AM

Thanks for the comments.

We are using a very simple filesystem layout:
sda: /boot = 100 MB, swap = 6 GB, / = 20 GB.
sdb: /app = 15 GB (or more depending upon use).

The underlying SAN storage is already RAID.

prowla · 02-11-2011, 06:18 AM

FYI, we decided to have it on LVM, so our basic build is:

sda1: /boot
sda2: LVM = /, swap
sdb1: LVM = /app