Tim Evans wrote:
On 01/28/2013 01:05 PM, xrx wrote:
On 01/28/13 21:27, James A. Peltier wrote:
| Does anyone know of any sort of Linux utility that does something | like what Solaris' Live Upgrade | (http://docs.oracle.com/cd/E19455-01/806-7933/index.html) does?
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Nothing really until BTRFS comes of age. I suppose you could snapshot your LVM volumes before performing the upgrade but to my knowledge there is nothing similar to Live Upgrade for CentOS
It does sound like you can do the roughly the same with LVM snapshots.
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Wheras with CentOS 6; you take a snapshot of the root partition (easy as "lvcreate --snapshot --name RootSnapshot --size 2G /dev/VolGroup/Root"), and then do an upgrade with a reboot. If it works; you're set, if not, just revert back to the snapshot (lvconvert --merge VolGroup/RootSnapshot) and reboot; you'd be back to the state before the upgrade.
Thanks. You also need to manage the grub and fstab configurations to allow the second boot environment to be visible, bootable, and mountable.
Actually, what we do, such as the upgrade from 5 to 6, is to create /boot/new and /new, rsync from an updated machine, then copy over /etc/sysconfig/network-scripts/ifcfg-eth* to the new, the /etc/ssh to the new, /etc/fstab, and, oh, yes, /etc/grub.d/rules/70-persistant-net.rules; then using zsh's files/modules(?) load that shell into memory, them create /boot/old and /old, move * old, mv lost+found, and /root back, then mv new/* ., Check /etc/grub.conf, and reboot.
If we need to go back - and we did on several, when we found out the speed issues to NFS-mounted home directories - mv * new, mv old/* ., sync, and reboot.
mark mark