Right after getting my SCSI cable problems fixed, I was all set to run some Bacula jobs. They immediately started failing:
27-Nov 12:59 bacula-dir JobId 112458: Start Copying JobId 112458, Job=CopyToTape-Diff.2012-11-27_12.58.05_08 27-Nov 12:59 bacula-dir JobId 112458: Using Device "DTL01" 27-Nov 12:59 kraken-sd JobId 112458: Ready to read from volume "DiffAuto-2357" on device "MegaFile" (/storage/compressed/bacula/volumes). 27-Nov 12:59 kraken-sd JobId 112458: 3301 Issuing autochanger "loaded? drive 0" command. 27-Nov 12:59 kraken-sd JobId 112458: 3991 Bad autochanger "loaded? drive 0" command: ERR=Child exited with code 1. Results=cannot open SCSI device '/dev/pass11' - Permission denied 0 27-Nov 12:59 kraken-sd JobId 112458: 3301 Issuing autochanger "loaded? drive 0" command. 27-Nov 12:59 kraken-sd JobId 112458: 3991 Bad autochanger "loaded? drive 0" command: ERR=Child exited with code 1. Results=cannot open SCSI device '/dev/pass11' - Permission denied 0
What does the permission on pass11 look like?
ls -l /dev/pass11 crw------- 1 root operator 0, 249 Nov 27 12:49 /dev/pass11
And what does bacula-sd run as?
# ps auwx | grep bacula-sd bacula 8249 0.0 0.0 26556 2436 ?? SsJ 2:37AM 0:00.05 /usr/local/sbin/bacula-sd -u bacula -g bacula -v -c /usr/local/etc/bacula-sd.conf bacula 8487 0.0 0.0 27040 3716 ?? Is 2:38AM 2:48.46 /usr/local/sbin/bacula-sd -u bacula -g bacula -v -c /usr/local/etc/bacula-sd.conf root 30719 0.0 0.0 9124 1160 0 S+ 1:05PM 0:00.00 grep bacula-sd #
There… bacula/bacula (You can ignore the bacula-sd on the first line; it’s running in a jail, as indicated by the J in the 8th column).
What are bacula’s group names etc?
# id bacula uid=910(bacula) gid=910(bacula) groups=910(bacula),5(operator)
OK, so /dev/pass11 is not readable/writable by bacula. I know it used to be. I recalled a system ability for altering device permissions at run time. It took a bit of hunting in /etc to located it, but I found /etc/devfs.conf. In it, I found this near the end:
# so bacula can access the autochanger via the operator group #perm ch0 0660 perm pass10 0660 perm pass11 0660
Don’t you just love comments?
So… why is this not working? As I documented in a previous post, after making changes to devfs.conf, or adding new devices to the system, you need to restart devfs:
[root@kraken /etc]# /etc/rc.d/devfs restart [root@kraken /etc]# ls -l /dev/pass11 crw-rw---- 1 root operator 0, 249 Nov 27 12:49 /dev/pass11 [root@kraken /etc]#
See? Now the permissions are adequate for Bacula.
I thought it would be interesting to document these entries from /var/log/messages because I had not noticed the portals notice before:
Nov 27 12:49:26 kraken kernel: sa0: <DEC TZ89 (C) DEC 2561< Removable Sequential Access SCSI-2 device Nov 27 12:49:26 kraken kernel: sa0: 10.000MB/s transfers (10.000MHz, offset 15) Nov 27 12:49:26 kraken kernel: ch0 at ahc0 bus 0 scbus12 target 0 lun 0 Nov 27 12:49:26 kraken kernel: ch0: <DEC TL800 (C) DEC 0326< Removable Changer SCSI-2 device Nov 27 12:49:26 kraken kernel: ch0: 10.000MB/s transfers (10.000MHz, offset 15) Nov 27 12:49:26 kraken kernel: ch0: 10 slots, 1 drive, 1 picker, 0 portals
