Elie Azar wrote: > Hi, > > I'm kind of new to Bacula, and definitely to Vchanger, so please bear > with me. > > I want to implement vchanger on a set of hard drives, with the idea that > I will have a pool of, let's say, 10 drives available for backup, and > where I do not have to specify a storage device for every job I define. > > One of the issue that come up right off the bat is the drive labeling. > In the "Removable Disk HowTo" document, they talk about labeling the > drives with the same label corresponding to the vchanger that these > drives are going to be attached to. Now, I am not using USB drives, but > rather fixed drives in a HD enclosure; so they will all be installed in > the system (Linux Gentoo). So, how will the system mount these drives, > all with the same label, and differentiate between them. Unless the > intention of the HowTo document was not to have the USB drives installed > at the same time. >
That is correct. Vchanger is designed for removable USB/Firewire/e-SATA etc. drives and treats the drive as a magazine of Bacula volumes. There can be multiple vchanger autochangers, where each autochanger would have its own config file. Each of these vchanger "instances" would have their own unique filesystem volume label (as opposed to Bacula label). Every drive belonging to a particular autochanger would have a filesystem labeled with that autochanger's label. The label is needed so that autofs can mount the filesystem at a predetermined mountpoint. Each autochanger may have only one of its drives (ie. "magazines") inserted at a time, just as a tape autoloader (of which vchanger is emulating) may have only one magazine loaded at a time. It is entirely possible, however, to configure 10 vchangers, one for each physical drive. Since vchanger initially places all volumes in the Scratch pool, if a drive fills up then Bacula will move a volume from the Scratch pool into the needed pool and use it. So that may do what you want. One problem is that there is no good way to reclaim the disk space after a volume is purged. Bacula does not delete the physical media, but only removes the catalog entries. That is probably the way it should be, and I'm not sure I've figured out a good way to handle that case. The best way is to carefully assign retention times such that enough volumes get recycled before they are needed. > The other issue is that, if that would work as is, and I have multiple > drives attached to the vchanger, these drives will be pooled, and thus > Bacula will backup on some volume form this pool, regardless of which > drive it belongs to. The question then arises as to what happens if the > backup job is larger that the balance of disk space on the chosen drive; > will the job span across multiple drives; i.e. it will start on a > certain drive, then the "Volume" will "grow" on another drive? I thought > that's how it worked with tape backups; bacula just went to the changer > and got a new magazine tape and continued the job. > If a vchanger's drive becomes full, then Bacula will look for another volume from the specified pool. In the case of a single vchanger, there is only one drive mounted at a time, so Bacula will issue an operator intervention needed message. > I may have this whole thing completely misunderstood, but I thought that > that was the intention. Pool together several drives, and tell Bacula to > backup to them, without having to specify a drive, and without having to > worry if there was room on a specific device, etc. > Not exactly. The primary reason was to be able to use removable USB drives in a plug and play fashion. > Any help would be greatly appreciated. > > Thanks, > Elie Azar > > ------------------------------------------------------------------------- > This SF.net email is sponsored by: Microsoft > Defy all challenges. Microsoft(R) Visual Studio 2005. > http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ > _______________________________________________ > Bacula-users mailing list > Bacula-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/bacula-users > ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2005. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ _______________________________________________ Bacula-users mailing list Bacula-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bacula-users
