I had worked in small company, and very often I do some stuff, related to system administration. Last week we were configuration FreePBX with Debian 7.8. While doing that we understood that server doesn’t want to be loaded from HDD, when anything is connected to the USB. Further research didn’t give any results. We decided to do the following:
- Backup the server
- Restore it on another server.
- Below you can find an easy way to do that.
I had two options:
- tar – zips all files and doesn’t save MBR -> backup will weight about 1.5GB
- dd – makes a full copy of the server -> with weight about 490GB.
For me it was easier to do tar, since the deploy and restore will be smaller. Also, in this case it’s possible to write down the backup even on a flash driver.
Here is the plan to do that:
- Create a backup
- Formatting and files system creation
- Backup restore
- MBR creation
- Backup creation Loading from a live flash drive.
Switching to root:
Mounting the section, which will be archived
mount -o ro /dev/sda1 /mnt
Mounting the flash drive to read/write:
mount -o remount,rw /dev/sdb1 /lib/live/mount/medium
Everything is ready to create archives:
ar -cvzpf /lib/live/mount/medium/backupYYYYMMDD.tgz --exclude=/mnt/var/spool/asterisk/monitor --exclude=/mnt/var/spool/asterisk/backup /mnt/
Parameters: c — create, v — process information, z —gzip archiving, p — data about owners, f — writing to the file, -/mnt/ — catalog, which should be archived.
The process takes about 7-10 minutes.
umount /mnt And rebooting
Restoring on a different hardware
2. Making file system
Loading from a live-drive and switching to the root:
Marking the disk with the help of cfdisk.
Deleting all sections. I have created two new sections: one 490 Gb for / (sda1) and one 10 Gb for swap (sda2). For the system one shoulw have type 83 Linux, the second – 82 Linux swap / Solaris. Mark the system one as (bootable) and save the changes.
Creating the file system
Mounting the sction
mount /dev/sda1 /mnt
Unzipping from the flash
tar –same-owner -xvpf /lib/live/mount/medium/backupYYYYMMDD.tgz -C /mnt/ <pre> Parameter –same-owner — saves owner and unzips, x — unzips from the archive, v — shows the info about the process, p — save access rights, f — indicates the file for unzipping, C — unzips in the category.
4. Creating MBR on a new disk
In order to create a boot record, mounting working catalogs to our root catalog. Mine, foe example, is /mnt. Catalogs /dev and /proc right now are used bu live-system, and we use bind parameter to get them available on both places: <pre> mount –bind /dev /mnt/dev mount –bind /proc /mnt/proc
Switching to a new system:
Making swap for a new system:
To make grub work, it’s necessary to give the right UUID for sectors in fstab, since right there is data of a previous system.
Opening second terminal under the root
Copying UUID to the current fstab.
There should be now problems if you install it on a clear disk. Updating the info from fstab
Getting back to Live system
Unmounting all catalogs
umount /mnt/dev umount /mnt/proc umount /mnt
Loading from a hard drive