Re: Verifying integrity of Backup Tapes
I was doing incrementals, and since my amverify failed on one of my tapes, I found that doing incrementals in my case is a bad idea if I can fit a full backup of all my data onto one tape. Now I am doing a level 0 on every run. Amverify get's to about the 6th filesystem I am dumping to tape and gives me an Input/output error. I know it's not the end of the tape, otherwise amdump would say so. FYI: These are travan 10/20 tapes. I know, not the best choice. I am trying to convince my boss to replace it with a DDS4 drive, as the DDS4 tapes are less expensive. These are $40 a piece, whereas the DDS4's are $13 a piece and hold twice as much data. Sincerely, Rick Duvall - Original Message - From: Technical Director [EMAIL PROTECTED] To: Rick Duvall [EMAIL PROTECTED] Cc: [EMAIL PROTECTED] Sent: Friday, October 31, 2003 9:03 PM Subject: Re: Verifying integrity of Backup Tapes Rick, I'm not to sure of a best method for checking the tapes, I might tar'ing a massive file to the tape and then back to see if it is working. Unfortunately during the use of your backup schema the tapes have to degrade. If it's a DLT400 tape or even a DDS# series I can see the need to hang on to them for some time to insure the cost of the media was repaid. Might it be best though to question the integrity of using a media that may have reached it's usable lifespan? As well depending on your method of backup, say full, 1/4, 1/2, 1/4, 1/8, etc. one tape that has a problem with the data on it will throw the entire sequence of backups. And if you have full backups, skipping the incremental, you might save yourself the hassle of a wrecked sequence of incrementals, yet the entire concept of backup is lost with bad media. I'm just trying to give you some ideas on how to go from here, not trying to critisize you on something you probably are already thinking. R. On Fri, 31 Oct 2003, Rick Duvall wrote: I have some backup tapes that I have been using each once per week for about 8 months. I am getting errors when running amverify on a couple of them. To be sure that my tapes are still good and not just the system giving me fits, it would be nice if I could run a program that would write bits to the tape in question and try to read them back, telling me which blocks on the tape are bad. Is there such a tool that does this? I guess it would be kind of like a scandisk is to a DOS Floppy as what I am talking about is to a Unix Tape. Sincerely, Rick Duvall Online Highways System Administrator (541) 997-8401 x 111 ___ [EMAIL PROTECTED] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to [EMAIL PROTECTED] ___ [EMAIL PROTECTED] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to [EMAIL PROTECTED]
Re: Verifying integrity of Backup Tapes
On Sat, 1 Nov 2003 02:31 pm, Rick Duvall wrote: I have some backup tapes that I have been using each once per week for about 8 months. I am getting errors when running amverify on a couple of them. To be sure that my tapes are still good and not just the system giving me fits, it would be nice if I could run a program that would write bits to the tape in question and try to read them back, telling me which blocks on the tape are bad. Is there such a tool that does this? I guess it would be kind of like a scandisk is to a DOS Floppy as what I am talking about is to a Unix Tape. Sincerely, Rick Duvall Online Highways System Administrator (541) 997-8401 x 111 ___ [EMAIL PROTECTED] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to [EMAIL PROTECTED] If I get errors on tapes I bin them immediately. Tapes wear and they do have a life span which varies from tape to tape. If you are backing up something it is obviously important so take no chances in loosing it. On my windows system I have the o/s backup set to verify to make sure the data is ok. When it crashed and had to be restored from tape I found that 2 of the tapes that were verified couldnt be read. The tapes were about a year old. The amount of money the company lost from having an old tape could have paid for a new server, several tape drives and media. The lesson I learnt was tapes are cheap, turn over frequently. Remember with dds technology they are a helical scan head. Tapes backed up on one dds drive are not necessarily readable by any other dds drive as I found out the hard way. Look at DLT as an alternative. Whatever you get make sure you add in a 3 year warranty. Get one from hp or ibm. We had our hp fail at 4pm. Had a new one on site 10am next day. They only fail when you really need them. ___ [EMAIL PROTECTED] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to [EMAIL PROTECTED]
Verifying integrity of Backup Tapes
I have some backup tapes that I have been using each once per week for about 8 months. I am getting errors when running amverify on a couple of them. To be sure that my tapes are still good and not just the system giving me fits, it would be nice if I could run a program that would write bits to the tape in question and try to read them back, telling me which blocks on the tape are bad. Is there such a tool that does this? I guess it would be kind of like a scandisk is to a DOS Floppy as what I am talking about is to a Unix Tape. Sincerely, Rick Duvall Online Highways System Administrator (541) 997-8401 x 111 ___ [EMAIL PROTECTED] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to [EMAIL PROTECTED]
Re: Verifying integrity of Backup Tapes
Rick, I'm not to sure of a best method for checking the tapes, I might tar'ing a massive file to the tape and then back to see if it is working. Unfortunately during the use of your backup schema the tapes have to degrade. If it's a DLT400 tape or even a DDS# series I can see the need to hang on to them for some time to insure the cost of the media was repaid. Might it be best though to question the integrity of using a media that may have reached it's usable lifespan? As well depending on your method of backup, say full, 1/4, 1/2, 1/4, 1/8, etc. one tape that has a problem with the data on it will throw the entire sequence of backups. And if you have full backups, skipping the incremental, you might save yourself the hassle of a wrecked sequence of incrementals, yet the entire concept of backup is lost with bad media. I'm just trying to give you some ideas on how to go from here, not trying to critisize you on something you probably are already thinking. R. On Fri, 31 Oct 2003, Rick Duvall wrote: I have some backup tapes that I have been using each once per week for about 8 months. I am getting errors when running amverify on a couple of them. To be sure that my tapes are still good and not just the system giving me fits, it would be nice if I could run a program that would write bits to the tape in question and try to read them back, telling me which blocks on the tape are bad. Is there such a tool that does this? I guess it would be kind of like a scandisk is to a DOS Floppy as what I am talking about is to a Unix Tape. Sincerely, Rick Duvall Online Highways System Administrator (541) 997-8401 x 111 ___ [EMAIL PROTECTED] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to [EMAIL PROTECTED] ___ [EMAIL PROTECTED] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to [EMAIL PROTECTED]
