[[PageOutline(2-5, Table of Contents, floated)]]

= Crin3 =

This is a 512M RAM Debian Stretch server for running S3QL and doing backups, it was installed on see ticket:11. This server has the other 3 servers, [[Crin1]], [[Crin2]] and [[Crin4]] mounted via SSHFS and it backups up selected directories using S3QL to [http://www.advania.com/datacentres/solutions/advania-cloud-services/ Advania].

== SSH Fingerprints ==

These were produced using the SshFingerprints script: 

{{{
1024 SHA256:MhmEY5TR0WWEdhAxtfi9b1e2Wrnj5ekeAOXjFbuein4 root@CRIN3 (DSA)
256 SHA256:Mqs3JBGtHeUL/5WywxqhDNpMcHG2s2ny5yldMLh3i7Q root@CRIN3 (ECDSA)
256 SHA256:mFH+00d5tCueuoD2Jrdll7PmP3vgtIzmjsvnosGAn14 root@CRIN3 (ED25519)
2048 SHA256:oybFehrgVMON4p62K6Zjg3pJ6wkCL9LzvTr0iEI01cg root@CRIN3 (RSA)
}}}

== Retrieving backups ==

If you need to restore a file or database from backups first mount the SQ3L filesystem for the specific server, for example:

{{{
sudo -i
mnt-s3ql crin1
}}}

This will mount the backups at `/media/s3ql/crin1` and you can then `cd` to the directory and list the backups, for example:

{{{
cd /media/s3ql/crin1
ls -lah
  total 0
  drwxr-xr-x 1 root root 0 Jul 23 12:18 2015-07-23_12:18:42
  drwxr-xr-x 1 root root 0 Jul 23 12:30 2015-07-23_12:22:12
  drwx------ 1 root root 0 Jul 23 09:58 lost+found
}}}

Database backups can be found in `/var/backups/mysql/databases` on [[Crin1]], they are produced by the 
wiki:DumpMysqlTables#backup-mysql script.

To copy files back to one of the other servers you can take advantage of the fact that they are mounted via SSHFS on [[Crin4]], and if they are not it is easy to mount them, for example:

{{{
sudo -i
mnt-sshfs crin1
}}}

Will mount the whole of the [[Crin1]] server at `/media/crin1` so retrieved files can be copied directly to the server. 

Once you have finished retrieving backup you can unmount the filesystem:

{{{
umnt-s3ql crin1
}}}

== Backup process ==

There is a root crontab which runs the backups each night:

{{{
# m h  dom mon dow   command
01 01 * * * /usr/local/bin/s3ql_backup crin1 
02 03 * * * /usr/local/bin/s3ql_backup crin2 
03 05 * * * /usr/local/bin/s3ql_backup crin4
}}}

First the S3QL file system is unmounted and checked (in case it has been manually mounted during the day) via wiki:S3QLMnt#unmnt-s3ql, then the remote server is mounted via SSHFS using wiki:SshfsMnt#mnt-sshfs and then the backup is run using a modified version of the [http://www.rath.org/s3ql-docs/contrib.html#s3-backup-sh S3QL backup script], wiki:S3QLBackup#s3ql_backup, this reads files with lists of directories to backup from `/etc/s3ql/` and calls the [http://www.rath.org/s3ql-docs/contrib.html#expire-backups-py expire_backups] script to delete old backups.

The contents of the files in `/etc/s3ql`:

=== crin1 ===

{{{
/usr/local
/etc
/home
/root
/var/backups
/var/www
/var/spool/cron/crontabs
}}}

=== crin2 ===

{{{
/root
/etc
/home
/var/www
/var/backups
/usr/local
/var/spool/cron/crontabs
}}}

=== crin4 ===

{{{
/home
/etc
/root
/var/www
/usr/local
/var/spool/cron/crontabs
}}}