On Fri, 2007-02-02 at 17:11 +0000, Matthew Stringer wrote:
I have 58 stand alone machines running Redhat 7.3
They run shared Apache, Exim, MySQL (nothing special).
they're all white boxes with dual P3 or P4 CPU's and local IDE disks in them.
They form a legacy platform that means they can't really be upgraded or the contents migrated off any time soon.
The problem I'm facing is that if a server fails I can't install 7.3 onto an new machine.
Currently use a Suse boot CD, boot into rescue mode, format drives and install GRUB, then copy a 7.3 image onto drive and boot it that way (needs a little tweaking to get it to work).
This worked for a while but I'm really struggling to get it to work now.
I'm thinking of buying new machines, running SUSE with Xen. Then run RH 7.3 as VM's and have a SAN with external storage.
Conceptually I can't see why it wouldn't work fine but I can't find any data to suggest how many VM's I can get on a server.
For example if I have 10 dual P3 1GHz servers will they all run fine on 1 new server with a dual quad-core Xeon CPU?
Hardware vendors I've asked don't seem to know for sure and I don't want to fork out for extra servers if they're not needed.
Any ideas, is there a rule of thumb for working this out?
Cheers
Matthew
Hi Matthew, Nice to hear ypu want to consolidate about 60 LAMP-machines based on RH7.3. One might indeed contemplate on buying some new iron and use it with XEN. Some thoughts however... Did you examine the combined systemload of all those 60 machines? How many DOM-u's are you considering to run on one machine? If you're willing to get quad-core's the cpu-load will probably not the problem. Memory is most likely the bottle-neck: Upto SuSE-10.0, i could run xen-images with as little as 128MB of memory each. With 10.1 and 10.2 i noticed that during an update the systems were swapping a lott and had to raise the memory for each DOM-u to 512MB each. So how much memory can your (new) system hold? Other point is, why do you want to stick to rh-7.3? Nothing against RH, but it is certainly NOT XEN-aware, So you either need machines with VT or Pacifica extensions, or upgrade the whole lot to a more recent distro. (I'm not sure whether FC6 is xen-aware right-out-of-the-box) Final point, have your xen images on a dedicated network storage, so you can migrated dom-u's for system to system: works like a charm, and have a real 0% down time! And use a seperate lan for it Hans -- pgp-id: 926EBB12 pgp-fingerprint: BE97 1CBF FAC4 236C 4A73 F76E EDFC D032 926E BB12 Registered linux user: 75761 (http://counter.li.org) -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org