[Bacula-users] LTO-6 - tape cleaning frequency
How often does your LTO-6 tape drive need to be cleaned? I ask because a recent post mentioned every 10 tapes. With my limited tape knowledge, that seems rather high, but I have no LTO experience. — Dan Langille signature.asc Description: Message signed with OpenPGP using GPGMail -- ___ Bacula-users mailing list Bacula-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bacula-users
Re: [Bacula-users] LTO-6 - tape cleaning frequency
On Nov 10, 2014, at 10:15 AM, Dan Langille d...@langille.org wrote: How often does your LTO-6 tape drive need to be cleaned? I ask because a recent post mentioned every 10 tapes. With my limited tape knowledge, that seems rather high, but I have no LTO experience. That frequency is incorrect. I misread the post, but I’d still like to hear how people deal with cleaning needs which arise *during* a job. — Dan Langille signature.asc Description: Message signed with OpenPGP using GPGMail -- ___ Bacula-users mailing list Bacula-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bacula-users
Re: [Bacula-users] LTO-6 - tape cleaning frequency
How often does your LTO-6 tape drive need to be cleaned? I ask because a recent post mentioned every 10 tapes. With my limited tape knowledge, that seems rather high, but I have no LTO experience. That seems excessive to me although I am still using a dual drive LTO2 autoloader. For that I run a cleaning cycle 2 times per year for each of the HP LTO2 tape drives. John -- ___ Bacula-users mailing list Bacula-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bacula-users
Re: [Bacula-users] LTO-6 - tape cleaning frequency
On 2014-11-10 07:32 AM, John Drescher wrote: How often does your LTO-6 tape drive need to be cleaned? I ask because a recent post mentioned every 10 tapes. With my limited tape knowledge, that seems rather high, but I have no LTO experience. That seems excessive to me although I am still using a dual drive LTO2 autoloader. For that I run a cleaning cycle 2 times per year for each of the HP LTO2 tape drives. John I have an IBM LTO-3 autoloader here. I just have a cleaning cartridge in the reserved slot in the library and I let it take care of itself rather than trying to do it on any sort of schedule. It loads the cleaning cartridge a couple of times a year. I bought this library used - when I first started using it I had to run cleanings every few weeks but they tapered off quite significantly after it had been in use for a while. The research I've done in the past on LTO technology has implied that you should never need to trigger a cleaning cycle on your own - the drive will let you know if it needs it. Cleaning tapes should only be used when the drive requests one. Our bigger library we had in the office ran for years without ever requesting a cleaning. It's worth mentioning that different manufacturers have different cleaning programs in their drives. For instance my IBM drive runs a much shorter cleaning cycle and has about 3-4x more cycles 'allowed' on a cleaning tape versus my HP drive I was using before it. My experience with my limited sample size of a half dozen LTO drives would seem to indicate that the IBM drive requests cleaning more often too. Also worth mentioning - the way your drive is used will have a significant impact on how many cleaning cycles it needs. If you aren't flowing data fast enough to it to keep it streaming at full speed it will build up a lot of cruft on the heads much faster. Bacula can help with this greatly by spooling data before writing, in particular with incremental backups that have many small files scattered all over the disk. Bryn -- ___ Bacula-users mailing list Bacula-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bacula-users
Re: [Bacula-users] LTO-6 - tape cleaning frequency
On Nov 10, 2014, at 10:15 AM, Dan Langille d...@langille.org wrote: How often does your LTO-6 tape drive need to be cleaned? Hi, I bought five cleaning tapes ten years ago. Four are on sale :o) HP LTO-3: Almost never, 7 years of operation HP LTO-5: Almost never, 2 years of operation 650 mounts, roughly 1 petabyte written 2 uses of cleaning tape, however I would bet that both were just my experiments with reading of cartridge memory Simply buy library, reserve one slot for cleaning tape, insert cleaning tape into and sing I don't care! I love it! I don't care! :o) You can look into /usr/src/sys/cam/scsi/scsi_sa.c. The timeouts are in minutes. Even IO has default timeout 4 minutes. Maybe the reason is possible cleaning? If you are really interested, please read http://www.tarconis.com/documentos/LTO_Cleaning_wp.pdf It is rather old, but many things still have to be true. It is from HP and it is possible that IBM is different. But I did not find similar document from IBM. The most important facts from the document above are: 1) The tape is flying over the head during the operation and the only contact is just when tape starts or stops. So yes, correct streaming is very important. Tape drive has to write data without repositions. 2) There is internal non-abrasive brush, which is usually sufficient. (From 150 km and LTO-1, I think that it may be preventively used after roughly 5 fully written tapes, but it is just my unconfirmed estimate.) 3) The cleaning tape is used practically only as a last resort and could not replace the brush - it is for another type of dirt. And it is abrasive, so if there is no reason to use cleaning tape, do not do it. Your head will be happier. Regards. -- Rudolf Cejka cejkar at fit.vutbr.cz http://www.fit.vutbr.cz/~cejkar Brno University of Technology, Faculty of Information Technology Bozetechova 2, 612 66 Brno, Czech Republic -- Comprehensive Server Monitoring with Site24x7. Monitor 10 servers for $9/Month. Get alerted through email, SMS, voice calls or mobile push notifications. Take corrective actions from your mobile device. http://pubads.g.doubleclick.net/gampad/clk?id=154624111iu=/4140/ostg.clktrk ___ Bacula-users mailing list Bacula-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bacula-users
