ESXi on USB Stick

philhoole

philhoole

philhoole

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I am tempting myself to have a play with the free VSphere and a lot of people have it booting from a USB stick. Indeed there is a nice little socket for such a thing inside the N40L micro server.

My simple question is, what is the big advantage on having ESXi on USB - Why not install it to a HDD in the system?

Surely a physical HDD is more robust and can't be accidentally removed.

I've played with it already as a VM in VMWare Workstation and installed a couple of guest OS without too much bother but decided the next step was to try it on its own dedicated machine but couldn't work out why I should want to boot from USB.

Suspect I am missing something blindingly obvious !
 
It does work! We've even tested removing the USB Key to see what happened and everything worked fine.

Flash memory is less likely to die anyway as it isn't moving (within reason).
 
The size of the ESXi install is pretty small, some people might prefer to have space for an additional physical drive in their raid array for the datastores if using local storage, some people might prefer to not buy a local disk at all if they are using shared storage and the only thing local is esxi
 
Using ESXi on flash media is a no-brainer really. As n3vrmind says, why use up a drive bay in your server that could be put to better use as part of the RAID VM storage volume or even run diskless servers which connect via Fiber or iSCSI to shared storage (such as a SAN)?

Server manufacturers clearly think it's a good idea as they've been building in internal USB ports or more rarely SD card slots. They'll even try and flog you a (overpriced) USB stick with ESXi preloaded with a nice vendor logo on it!
 
There is no reason not to run it from flash, It has no performance increase from a disk install and it saves a drive bay/channel. I'm under the impression that when ESXi is running it is fully memory resident anyway, I wouldn't be surprised if it carried on running fine even if you did accidentally remove the memory stick. And based on the fact that it reads and writes so infrequently I'd say flash media is likely to be significantly more robust than a traditional platter drive.

edit: Just noticed Ringiho already mentioned that it carries on working with the flash media removed
 
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I was speaking to the guys in #vmware on freenode last night about this very topic. They suggested just using a usb stick and new hp dl385 g7 has internal usb ports and sd card slots. I suggested using a 16gb ssd that you can get for £25 and they said that it would be waste of the ssd. They said buy a 4gb usb stick and that should be sufficient. One guy even said that you don't need any media and that he uses bootP for esxi.
 
I've not tried it, but vSphere 5 can PXE boot all the way from bare metal to a fully configured ESXi host, no need for any local storage :)

If you search for the procedure to extract the ESXi imagedd file to USB/SD using WinImage, you'll see how small the ESXi footprint is. Really would be a waste of HDD(s).
 
K@rl said:
anyone got a link for a lazy man? Doing this next week and want to see my disks free
Click to expand...

For installing to USB key, you just plug it in and run the installer on the machine. It just picks it up as a normal disk and away you go!
 
Works like a charm - much better than running W7 with VM Server 2. Had some strange networking issues with that.

Thanks again :)
 
Ringiho said:
For installing to USB key, you just plug it in and run the installer on the machine. It just picks it up as a normal disk and away you go!
Click to expand...

It certainly does, I have installed it this way just now!

Works like a dream.
 
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