Backup

Intended audience: End User and VSHNeer

Linux Servers Backup

Software

The software used to create backups is BURP (BackUp and Restore Program).

The backup runs in multiple phases:

Phase Client Server Client Impact

0

Running pre-backup scripts (for example, dump databases)

n/a

Degraded disk I/O performance

1

Filesystem scan and send new stats (files, inodes, sizes) to the server

Receive stats from the client

Degraded disk I/O performance

2

Send the changes that the server requests. The work of the client is now finished.

Request and receive changes from the client and create an unchanged list and a changed list.

Depending on available bandwidth this might have an impact on network I/O performance

3

n/a

Generate the new manifest list for the backup out of the unchanged list and the changed list.

n/a

4

n/a

Finish off the backup by jiggling the received data around and putting everything in the correct place.

n/a

Schedule

Backup runs daily between 22:00 and 07:00.

Contents

Default file set

The following directories are backed up on every server:

/boot/grub
/etc
/home
/usr/local
/var/backups
/var/lib/dpkg
/var/log
/var/spool

Additional backup configuration

Depending on the software running on the server additional directories will be backed up. These come from the puppet profiles. In order to get a complete list of files that are backuped, execute the following command:

$ egrep -h '(in|ex)clude' /etc/burp/burp* | sort

This will output a list of all directories included and excluded in/from the backup.

Pre / Post backup scripts

In order to have consistent backups, its necessary to run some pre-backup tasks. These may include dumping/locking databases, clear logs etc. To find out what jobs will be running, execute the following command:

$ ls -l /usr/share/burp/{pre,post}-backup/

This will output a list of all script that are run before and after the backup.

For details on database backups see the following articles:

Retention

We use the following retention policy:

  • Keep the last 7 "daily" backups;

  • Keep the last 4 "weekly" backups;

  • This guarantees to keep 7 backups in a row, plus 4 on multiples of 7.

Check the detailed description in the BURP documentation.

Location

In the default configuration managed servers are configured to backup to a off-site server. The following table lists the shared backup servers and their location:

Name Hardware Owner ISP Location

backup1.cloudscale.vshn.net

VSHN AG

cloudscale.ch AG

e-shelter datacenter, Rümlang, Switzerland

backup9.lpg.cloudscale.vshn.net

VSHN AG

cloudscale.ch AG

green.ch datacenter, Lupfig, Switzerland

backup10.lpg.cloudscale.vshn.net

VSHN AG

cloudscale.ch AG

green.ch datacenter, Lupfig, Switzerland

backup11.lpg.cloudscale.vshn.net

VSHN AG

cloudscale.ch AG

green.ch datacenter, Lupfig, Switzerland

backup12.lpg.cloudscale.vshn.net

VSHN AG

cloudscale.ch AG

green.ch datacenter, Lupfig, Switzerland

To find out which backup server is used, check the server line in the burp client configuration:

$ egrep '^server\s+=' /etc/burp/burp.conf

Encryption

  • All data is encrypted on the client and the encrypted data is then sent to the backup server

  • The data transport between the client and server is done over a TLS-encrypted connection