Guest Performance Question (HDD)

DeaconFrost said:

I'm in the process of building an ESXi setup at home. I will list the specs at the bottom, but my main question comes down to VM performance when running from a spinner HDD. ESXi is running from a 16 USB flash drive. I have an old 64 GB SSD for storing .iso files. Now, the question is, how will the VMs perform if I have them stored on a drive like a WD 2 TB RED.

Intel Core i7-3770K
Gigabyte Z77 board
32 GB DDR3 memory
Server grade, ESXi compatible 4 port GB NIC

Mainly, I'm going to use this as a test setup, running an Ubuntu VM for learning, maybe 2 Windows 2016 servers, and a Windows 10 VM for software testing.

Hi there

@DeaconFrost

running Esxi is a very tiny OS so the VM's should be OK -- use RAID 0 on the linux VM's if you've got two spinners. You'll need to install (probably already there by default but check) the Linux Software RAID module mdadm. You build your array say mdtest1 and then mount (as root) mount /dev/mdtest1 -t auto -o rw /mnt/DV1 or wherever you want it mounted. Using SAMBA other machines on your network (including Windows) should be able to access your (VM) HDD's with no problems.

Linux software RAID is excellent --well worth using --for more info google MDADM. Install as well package system service manager (SSM) so you can run ssm commands -- makes it really easy to see what's mounted and where (ssm -list as root).



I suspect though even if you only have 1 HDD the Linux VM's should perform OK -- Windows Guests might be a bit of a dog though. Having to manage the VM's and logon via a 2nd machine rather than doing it on the local server which has the VM's on it makes using ESXI as a home lab rather cumbersome but if it's fine by you the overhead of the esxi OS is really minimal.

The main problem with esxi for home users is that you'll need a separate Laptop / desktop to access and control your guests under ESXI. I'd look at possibly using something like a full Linux system which will easily boot from a flash drive -- what you need to do is simply install the boot loader (/boot) on the flash drive and the rest of the OS on any hard drive. That way you can have a GUI also in the Linux system.

Also ensure you have ntfs-3g installed on your Linux VM -- it usually is by default but check --this allows read / write access to Windows NTFS directories.

Don't install the whole OS on a flash drive --all you need is the boot loader and install it on /boot. Install /home and / (root)on other devices --don't forget swap file as well. !!!

Distros like CENTOS (which is what I use) and SUSE make that very easy. Install /home and / on HDD.

In my example my NAS server has the /boot on an internal micro sdhc card (/dev/sdc1) and I have the rest of the OS loaded on to an SSD -- this server won't boot from the SSD port (was an old DVD port) unless the server is in RAID mode -- which is terrible --HP's "Fake Raid" -- much better to switch to AHCI mode , boot the boot loader from the micro SD card and load the rest of the OS onto the SSD where after boot the entire thing runs from the SSD and performs really fast.

I have then 4 Standard HDD's split into 2 X RAID 0 arrays via mdadm. I only want sped here so RAID 0 is fine --I take enough backups if things get broken and the speed advantage of RAID 0 is simply overwhelmingly positive. - In my case I have 2 pairs of equal capacity drives --however Linux software RAID doesn't insist for RAID 0 that the drives have to be of equal capacity).

I did think of Esxi but having to use a separate machine as a console to manage and logon to the VM was a real pain. Being able to logon to the actual server IMO is better for a home user. With Centos / ubuntu / suse etc you can easily install vmware and run Windows VM's -- or you could run a windows host with linux VM's say using HYPER-V. The disadvantage of a Windows host is that you wouldn't be able to boot from the external flash drive,

Cheers
jimbo