<html><head><style type='text/css'>body { font-family: 'Arial'; font-size: 12pt; color: #000000}</style></head><body><br><br>----- Original Message -----<br>From: "Frank Cox" <theatre@sasktel.net><br>To: centos@centos.org<br>Sent: Tuesday, December 18, 2007 2:55:49 PM (GMT+1000) Australia/Brisbane<br>Subject: Re: [CentOS] "multi-boot" drive partitioning<br><br>On Tue, 18 Dec 2007 14:48:57 +1000 (EST)<br>"redhat@mckerrs.net" <redhat@mckerrs.net> wrote:<br><br>> I don't understand what you are trying to achieve. Some sort of (poor mans) redundancy at the hard disk level <br><br>A spare computer that can be swapped in to replace any of 4 other computers<br>without requiring a lot of setup between "the main machine died" and "the<br>spare is now online."<br><br> ? When would the "webserver quit" ? E.g. if your<br>motherboard dies then it doesn't matter how many copies of an os you have<br>spread over how many disks, the whole thing is unavailable. <br><br>That's when you whip out the spare computer, plug it into the network, boot it<br>up and hit "1" to load the webserver, and then take the main webserver machine<br>apart and find out why it died at your leisure. At least, that's the idea.<br><br>> Why not mirror the two 300gb drives, using software raid and install the centos virtualization and run any number of vms *all the time* ?<br><br>Because the spare machine may have to replace any of 4 different computers that<br>live on two separate networks. There is no need to have a second webserver<br>running, for example, until the main webserver quits. If it quits, it would be<br>nice to have another one all set up and ready to plug in. Boot up, restore the<br>webpage data from last night's backup, and put it online. I want to have<br>Apache set up and everything else on the spare machine before the problem<br>arises.<br><br>Same for the fileserver, the LTSP server, and so on. One spare machine that<br>has 4 "personalities", as required.<br><br>-- <br>MELVILLE THEATRE ~ Melville Sask ~ http://www.melvilletheatre.com<br>_______________________________________________<br>CentOS mailing list<br>CentOS@centos.org<br>http://lists.centos.org/mailman/listinfo/centos<br><br>-- <br>This message has been scanned for viruses and<br>dangerous content by MailScanner, and is<br>believed to be clean.<br><br><br><br><br>Ahaaaaa.......<br>
<br>
now I get it.<br>
<br>
You have another computer, which, I presume, is exactly the same as the 'live' one ? <br>
<br>
I'd
still bet my money on the the fact that you'd spend more time rooting
around with installation, backups and restores than if you setup
software mirroring and used virtualization. Picture this;<br>
<br>
1) install centos 5.1 including virtualization on mirrored 300gb hdds<br>
2) install any number of vms<br>
3a) server dies due to faulty component - remove both hdds and place in second server boot up and all vms will be running<br>3b) hard drive in server fails - do nothing as it is mirrored<br>
<br>
I reckon step 3a could be done comfortably in under 15 minutes.<br>
<br>
How does this compare to your solution with regards to complexity and system availability ?<br>
<br>
Also,
once you were happy with the virtualization setup you could run both of
your machines in a 2 node cluster and have little no or downtime when
hardware fails.<br><br>Cheers.<br></body><br />--
<br />This message has been scanned for viruses and
<br />dangerous content by
<a href="http://www.mailscanner.info/"><b>MailScanner</b></a>, and is
<br />believed to be clean.
</html>