Difference between revisions of "Backup"

From PrgmrWiki
(merge Editing Backing up disk image via SSH.)
(remove obsolete x-refs now that pages are merged.)
Line 27: Line 27:
  
 
Which has the added benefit of downsizing the partition to its smallest possible size (i.e., completely full), so if you are restoring to a smaller device, you will not fill up the device with unused space.
 
Which has the added benefit of downsizing the partition to its smallest possible size (i.e., completely full), so if you are restoring to a smaller device, you will not fill up the device with unused space.
 
(see [[Backup]] for more on backups in general, and [[Restore]] to restore this image)
 
  
 
{{u}}
 
{{u}}

Revision as of 19:04, 28 June 2017

What are some ways to backup the vps? How should a backup be done while in the rescue image or while the vps is running?

A full backup is only possible while in the rescue image, and there is often not enough tmp space to use as a destination, so it needs to be copied over the network directly to the destination. One way is to setup a special account with its own password or ssh keys on the backup destination server, then pipe tar or gzip through ssh. This works with a filesystem image directly from or to a partition, or with tar and a mounted filesystem. (Some more details: Backing_up_disk_image_via_SSH)

Editing Backing up disk image via SSH

backing up new system to another server ...

my current procedure to grab compressed disk image:

  • boot to Centos rescue image (described on the Password Reset page)
  • mkdir /tmp/xvda1
  • mount /dev/xvda1 /tmp/xvda1
  • dd if=/dev/zero of=/tmp/xvda1/big_blank_file
  • rm /tmp/xvda1/big_blank_file
  • umount /tmp/xvda1
  • bzip2 < /dev/xvda1 | ssh me@my.other.server.tld "cat > xvda1_backup.bz2"

(The "big_blank_file" finagling for compressability may be not particularly necessary on a fresh image ...) With the zero-pad prep, a fresh Debian Lenny image (about 500 MB installed on a 12 GB disk) compresses down to less than 185 MB. After installing Apache2 and some user data, the disk image compressed from about 750 MB down to about 250 MB - without repeating the zero-pad prep.

Alternatively, you might do something like this:

  • boot to Centos rescue image
  • e2fsck -f /dev/xvda1
  • resize2fs -M /dev/xvda1
  • bzip2 < /dev/xvda1 | ssh me@my.other.server.tld "cat > xvda1_backup.bz2"

Which has the added benefit of downsizing the partition to its smallest possible size (i.e., completely full), so if you are restoring to a smaller device, you will not fill up the device with unused space.

Also, see Restore