Mirroring Disk.

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OK all my HP Microserver is purring away nicely now, as usual I
looking for the rainy day.

Although my data is on a RAID 5 array my OS is on a single disk.

Any suggestions as to the best way to have a copy of my OS on an attached USB Drive?

Been considering dump and restoring to the usb disk periodically? or maybe something using LVM or maybe creating and breaking a RAID 1
array?

Just not sure of the best plan at the mo.

Any tips?

One thought on - Mirroring Disk.

  • It really depends on your use case. Are you looking to keep the OS
    running if your disk fails? If so you need a real RAID (using real disks, not a USB drive). Are you looking to be able to do a very fast restore and be mostly up to date with what you had before? If so a filesystem-level dump might work. Are you looking to simply be able to restore a file you botched by accident? If so something like rsnapshot might work. Are you just looking to get back up and running? If so one way to go could be rsnapshot and kickstart–kickstart to automatically install the packages you need without needing to go through the full install prompts, and rsnapshot to capture your local config files and software (likely primarily in /etc, perhaps some in
    /usr/local or /opt). (Or you can just record a list of your packages somewhere offline, and make sure you install them, if you don’t want to mess with kickstart.)

    Constantly making and breaking a RAID1 with a USB drive is probably not helpful. It’s just more wear and tear on the OS drive, because it has to be constantly read in order to mirror the target drive, and your USB
    drive is probably not what you want to boot off of if your system drive fails. You’d be much better off with a permanent RAID1, but if you can’t do that then at least make a RAID1 to a USB enclosure which contains the same size and interface drive as your current system disk. This way if it fails you can swap in the backup drive and not have to boot from a USB drive.

    –keith