atom feed23 messages in com.redhat.linux-lvmRe: [linux-lvm] Using LVM Mirroring t...
FromSent OnAttachments
Ambrogio De LorenzoSep 16, 2009 6:59 am 
André GillibertSep 16, 2009 8:05 am 
Ambrogio De LorenzoSep 16, 2009 9:47 am 
Brian J. MurrellSep 16, 2009 9:58 am 
mala...@us.ibm.comSep 16, 2009 11:19 am 
Ambrogio De LorenzoSep 16, 2009 12:03 pm 
Ambrogio De LorenzoSep 16, 2009 12:15 pm 
Brian J. MurrellSep 16, 2009 12:49 pm 
André GillibertSep 16, 2009 1:03 pm 
Ambrogio De LorenzoSep 16, 2009 1:22 pm 
mala...@us.ibm.comSep 16, 2009 1:33 pm 
Kai Stian OlstadSep 16, 2009 3:03 pm 
Bryn M. ReevesSep 17, 2009 2:57 am 
Stuart D. GathmanSep 17, 2009 8:06 am 
Brian J. MurrellSep 17, 2009 8:34 am 
Stuart D. GathmanSep 17, 2009 3:49 pm 
Les MikesellSep 17, 2009 4:26 pm 
Brian J. MurrellSep 17, 2009 4:48 pm 
Stuart D. GathmanSep 17, 2009 5:57 pm 
Sven EschenbergSep 17, 2009 6:51 pm 
Stuart D. GathmanSep 17, 2009 6:55 pm 
Mark H. WoodSep 18, 2009 9:05 am 
Stuart D. GathmanSep 18, 2009 12:12 pm 
Subject:Re: [linux-lvm] Using LVM Mirroring to obtain a usable backup
From:Stuart D. Gathman (stu@bmsi.com)
Date:Sep 17, 2009 5:57:59 pm
List:com.redhat.linux-lvm

On Thu, 17 Sep 2009, Les Mikesell wrote:

Stuart D. Gathman wrote:

Those with money to burn seem to favor SANs. (And cloning a PV with a SAN and importclone is an easy solution to the OP problem - if only they had a SAN.) I'm part of the Po' Fo'k contingent.

Is a SAN something you can emulate with an iscsi target on fairly normal equipment?

It depends on the software on the SAN server having something like a snapshot or mirroring facility available. At its simplest level, a SAN server can be just a disk accessed by iSCSI or ATAoE. (And even I can afford that.) But high end SAN servers are LVM systems (using something like ZFS) and clients attach to logical drives that can be cloned, snapshotted, etc. Kind of moves the whole LVM layer to the disk subsystem (although it is still useful to have an additional LVM layer locally). More people people buying high end SAN servers might have kept Sun from getting bought by Oracle :-)

A high end SAN server means you allocate "disks" from the SAN instead of buying physical disks. Adding another "disk" to a server can be as simple as allocating another "LV" (or whatever the SAN software calls it) and attaching it. The OP would simply clone his disk in the SAN (and needn't worry about the duplicate VGID as long he doesn't attach the clone) before doing the upgrade.

I have one client with a SAN system, and it seems to perform well. It is one client that never needs to install a physical disk on a server I maintain for them. (Caveat, booting from iSCSI requires bringing up a Nic - which is tricky to do for linux in initrd.)