Using an Autochanger

BWeb permits graphically administering your autochangers using mtx.

Bacula Configuration

Your autochanger as well as its drives, if there is more than one, must be defined in the Director’s configuration file. Our example will use an LTO3 changer with three drives: LTO3_0, LTO3_1, LTO3_2. All these three drives will be defined in three different Storage resources in the Director configuration file.

Storage {
 Name = LTO3
 ...
 Autochanger = LTO3
}

Storage {
 Name = LTO3_0
 ...
 Autochanger = LTO3
}

Storage {
 Name = LTO3_1
 ...
 Autochanger = LTO3
}

Storage {
 Name = LTO3_2
 ...
 Autochanger = LTO3
}

Hardware Access

BWeb doesn’t use Bacula to do physical operations on media, you have to configure BWeb to be able to use system commands. Under normal circumstances, the web users can’t access drives or an autochanger directly. It is possible to configure sudo with visudo for that purpose.

# grep mtx /etc/sudoers
www-data ALL = (root) NOPASSWD: /usr/sbin/mtx -f /dev/changer transfer *
www-data ALL = (root) NOPASSWD: /usr/sbin/mtx -f /dev/changer status
www-data ALL = (root) NOPASSWD: /usr/sbin/mtx -f /dev/changer load *
www-data ALL = (root) NOPASSWD: /usr/sbin/mtx -f /dev/changer unload *

If you are using bacula account with lighttpd to run the web server, bacula should be a member of the tape group, and you don’t need sudo configuration.

Remote Autochanger

If you want to use a remote Storage Daemon, you can use ssh to remotely access your autochanger from your web server. You will need to configure an ssh key exchange between your web user and an authorized user that can use the hardware (directly or with the sudo command). You will have to configure ssh as pre-command under BWeb (see figure 14). An example could be to use ssh bacula@storage1.

BWeb Configuration

Before you begin using BWeb, you must define a location with the same name as your autochanger (Cf. Managing Volume Locations). Through the Setup menu, you will be able to declare your autochangers in BWeb as shown in figure 13.

To be able to work, BWeb has to know your autochanger configuration, especially the drive order — Drive Index in the Storage Daemon configuration — see figure 14.

Figure 14: Definition of an autochanger

Go back to Installation with Packages chapter.