While I am not completely new to running instances in KVM/Qemu, I am a total
noob when it comes to clustering.
While I realize that not all of these questions pertain specifically to the
oVirt project, I would much rather get input from people that have experience
in this environment.
I am in the process of designing my next server farm and would like to know
some basics that I can't seem to find the answers to via google search.
Background:
I have a server farm setup for a large family. It consists of 9 servers
(minimal-to-medium loads for the most part, but they are in poor condition
physically). My hopes are to run this same setup virtually in a 3-node
cluster. I can run the entire farm in a virtual environment on a host with a
dual, quad-core box with 64gig RAM. That said, I know that each of these
nodes will be capable of handling the entire load by itself if absolutely
necessary.
For disk space, my hopes are to use two drive arrays (10 configuration?) which
I can build (up and out) from without having too much trouble.
Everything will be fiber, including drops to the computers and televisions.
Copper will exist as well for things like POE, printers, etc. (but not in
scope)
Questions:
1. As I understand it, a N-to-N configuration means that there will be load
balancing between the nodes as well as failover. Is the load balancing
something that is manual (I have to monitor/balance the load manually, or is
it done automatically?)
2. If it is done automatically, how do the loads get split up? Is the
virtual machine itself the unit of load that transfers from one node to
another or does it go so far as balancing services running inside those
virtual machines?
3. For the fail-over, is it seemless in the sense that the user's connections
don't get reset or is there a short period of down-time before the service is
available again? While this isn't a big issue for me, it is something that
I've been wondering about.
4. Fibre channel or FCOE? (I've spent entire evenings trying to get a
straight answer through google searches, but there seem to be way too many
agendas). Being that one of the virtual servers will be a media server for
the televisions (new addition), my worry is lag-time (I would like to serve at
least 5 televisions without lag-time). The array will also support things
like file server, space for about 2-dozen www (family pages (lots of
pictures)), space for mail, space for backups (rSync,Amanda), ISO boots, etc.
I have the logical and physical topology drawn up for the most part, but until
I understand a bit more, I'm scared _less about dropping any money into the
project because I've neither seen a setup like this in action, and what I find
online seems a bit vague in the way of details (dumbed-down enough for the
likes of me to know if the hardware I'm buying is necessary and/or sufficient to
achieve my goals).
Any and all pointers, suggestions, patience, etc. would be greatly
appreciated.
mchauber