Building a Server...Again

[Twinpeaksr]

As Knavish explained, there is is no such thing as a "host VM" with KVM. The host is just a normal Linux operating system. I assume that by "network VM" you mean DNS, DHCP, etc and by "routing VM" you mean the actual router, firewall, and proxy.

I think the confusion is that I have been using the term Host VM. What you have describes is what I thought Host VM was, guess I will correct my terminology and make it clearer to others!

There is no real reason to put normal files inside a zvol. Just make a normal ZFS filesystem (zfs create zpool1/myfiles).

This makes sense.

I can understand this somewhat, but in the event of a disaster, you should be able to turn your host OS into a router/NAT box in about 5 minutes. (You will be backing up your network configs, won't you?)

I should, but reality is not a kind mistress and what I should be able to do, I seldom can do. Though backing up network configs is a good idea...

I would like to point out that you actually decreased the size of the cache device from my recommendation. I recommended 80GB, you are specifying 48GB.

Stop pointing on my faults!! :whiste:

The ZIL log device is not a write cache per se in that it is never read from except in the case of an unexpected crash. Writes are actually cached in DRAM and written out to the log device "just in case". The writes are flushed directly to disk from DRAM.

Anyway, there is no reason to make a log device more than 8GB, even on a huge system. There is certainly no reason to make it equal in size to main memory. This is because the log only needs to keep dirty (written) bits since the last flush to disk. By default, ZFS will sync every ~4 seconds, so the log device only needs to be big enough to keep the last 4 seconds worth of writes. For an 8GB log, that works out writing at a rate of 2GB/s, which you'll never be able to do anyway. So 8GB is already very safe, 16GB is just wasteful.

So...8GB it is.

Knavish explained this well, but to reiterate: There is no such thing as a "host VM" in a KVM setup. The host is just a normal Linux system and the VMs run inside KVM processes on the host. It is similar to something like VirtualBox or VMWare Workstation like Knavish pointed out, except with an important difference: there are tools for managing the VMs so that you don't have to literally open up a graphical application in order to get access.

I agree, he did a great explanation, confirming what my research determined. This is the last key that I needed, now things make sense!

Happy to help.

Thanks again, this has helped greatly! Will be starting build soon, and we will see how I retain my new knowledge!