Hi John. No software compression is enabled in bacula. Files are basically compressible files, such as MS Office, engineer drawings, images, text files, etc. Just a fraction of them are compressed files (.ZIP and .RAR), not more than 5%.
Regarding your second comment I guess it could be the case and it is also worth of some more analysis. When bacula reaches the end of the tape, does it tell you or log the block where it has stopped? I know that a 'mt -f /dev/nst0 status' would return the current block position, but I would like to know if bacula does it too. Also, is there a way to check how many total blocks the operating system or bacula are seeing on the tape? Regarding this last question, is tapeinfo's MinBlock/MaxBlock information reliable enough to conclude that this tape has a total of 16,777,215 blocks? [r...@br01 /usr/share/doc/mt-st-0.9b]# tapeinfo -f /dev/sg1 Product Type: Tape Drive Vendor ID: 'IBM ' Product ID: 'ULTRIUM-HH3 ' Revision: '93G7' Attached Changer: No SerialNumber: '1H10077966' MinBlock:1 MaxBlock:16777215 SCSI ID: 6 SCSI LUN: 0 Ready: yes BufferedMode: yes Medium Type: 0x38 Density Code: 0x44 BlockSize: 0 DataCompEnabled: yes DataCompCapable: yes DataDeCompEnabled: yes CompType: 0x1 DeCompType: 0x1 BOP: yes Block Position: 0 [r...@br01 /usr/share/doc/mt-st-0.9b]# Cheers, Rodrigo -----Original Message----- From: John Drescher [mailto:dresche...@gmail.com] Sent: Wednesday, September 01, 2010 3:44 PM To: Rodrigo Ferraz Cc: Brian Debelius; bacula-users Subject: Re: [Bacula-users] RES: RES: LTO-3 tape not compressing data/premature end of tape space > Yes John, they are LTO-3 tapes. > Is your data already compressed (.zip, .bz2, .7z, .mpeg ...)? Or is software compression enabled? If not I am not sure. Bacula does not directly control the drive. It relies on the OS to tell it that the tape is full. Well actually this process is not even that clear. The streaming tape drive reports a write error when it can not fit a block on the tape. When bacula sees this error it checks that the last block was written successfully and then marks the tape full. John ------------------------------------------------------------------------------ This SF.net Dev2Dev email is sponsored by: Show off your parallel programming skills. Enter the Intel(R) Threading Challenge 2010. http://p.sf.net/sfu/intel-thread-sfd _______________________________________________ Bacula-users mailing list Bacula-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bacula-users
