Re: My Monthly archive config - issue (Trying to source and use a tape changer if possible)
Chuck Amadi Systems Administrator wrote: I have found a SCSI tape drive spec below it was once used for backups prior to moving over to Amanda. External Seagate DAT subsystem for NT, Windows, NetWare, DDS-3 recording format, consists of STD124000N DAT drive (data transfer rate 2.2 MB/s, 24 GB capacity with DDS-DC data compression), tabletop enclosure, tape, 1 m cable with 50pin high density plug, Thus could this possible be used a a tape changer I have checked the Amanda homepage but doesn't mention any devices. I'm not acquainted with the device described above, but the description doesn't mention anywhere that it's a changer. Looks more like an external tape drive. If you can connect this to your existing backup server as a *second* tape drive, then you can most likely setup Amanda to use both drives. I've read that Amanda has a changer script for this purpose, called chg-multi, but I haven't used it with real tape drives myself. --- ... Error reading FAT record: Try the SKINNY one? (Y/N)
Re: My Monthly archive config - issue (Trying to source and use a tape changer if possible)
Chuck Amadi Systems Administrator wrote: I am using DDS-4 DAT tapes 20GM native and 40GB compression So I hope amanda using and amanda, using gzip, can probably put well over 40GB on the tape if your are correct. No, that won't work out. First of all, 40GB compressed is a purely imaginative figure that marketing pinheads have come up with in order to impress clients. It has no basis in reality; in fact they assume that your data is compressible (which might or might not be the case, but read on), and that it compresses at a 2:1 ratio (which will not be the case in real life). If you plan to use software compression via gzip, the data you feed to the tape is not compressible at all; the DDS' hardware compressor will actually expand the data before writing to tape, giving you an effective capacity of much *less* than 20GB after gzip compression, or just a little more than 20GB before gzip. Just use one *or* the other of hardware and software compression; general consensus on the list is that software compression is better if you can spare the cycles. Look in the archives for reasons if you are interested. Alex -- Alexander Jolk * BUF Compagnie * [EMAIL PROTECTED] Tel +33-1 42 68 18 28 * Fax +33-1 42 68 18 29
Re: My Monthly archive config - issue (Trying to source and use a tape changer if possible)
Hi Gene I am using DDS-4 DAT tapes 20GM native and 40GB compression So I hope amanda using and amanda, using gzip, can probably put well over 40GB on the tape if your are correct. Cheers On Fri, 2005-09-30 at 11:33 -0400, Gene Heskett wrote: > On Friday 30 September 2005 08:09, Chuck Amadi Systems Administrator > wrote: > >Hi all and Scott > > > >I am trying a Monthly archive but in order to follow a setup similar to > >Scott I need a tape changer. > > > >I have found a SCSI tape drive spec below it was once used for backups > >prior to moving over to Amanda. > > > >External Seagate DAT subsystem for NT, Windows, NetWare, DDS-3 > >recording format, consists of STD124000N DAT drive (data > >transfer rate 2.2 MB/s, 24 GB capacity with DDS-DC data > >compression), tabletop enclosure, tape, 1 m cable with 50pin > >high density plug, > > > >Thus could this possible be used a a tape changer I have checked the > >Amanda homepage but doesn't mention any devices. > > > >Cheers > > > >Chuck > > It should work just fine, Chuck, as long as thats a large enough > tape. With hardware compression off, it will hold 12GB, and amanda, using > gzip, can probably put well over 24GB on the tape. > > The only caveat is the tape format. Its cheap, and in DDS2's at > least, I had tape trouble after 20-50 passes per tape. They claim a > million passes, but the drives heads are worn out long before that in > my experience. Rotary heads, are like your vcr in design, and the > lifetime is measured in a small number of thousands of hours, like > 3 to 5 for the life of the head. I've had maybe 1% of the problems I > had with DDS2 tapes since I switched to the FILE device on a 200GB drive. > > For rotating heads, the head wear and damage occurs as each head tip > engages the edge of the tape at the start of the track, there is tape > contact and bounce there, but once 'on' the tape, there is a micron > thick air cushion between the tape and the head tip. Its that crash > at the entrance edge of the tape that does the damage. I've looked > at tips that were actually shattered in my many years of keeping > broadcast recorders going. DVC-PRO heads are 1/3rd the size of a dat > head, and they can read and write 100 MB/second these days. But the > electronics in those is 1000x smarter in terms of error correction > too. And the error correction doesn't have to be 100%, as long > as the pixal coming out somewhat resembles what went in, thats good > enough, the eye is a whole lot more forgiving than data storage. > > Todays tape drives are still in the horse and buggy era in comparison. > > >On Fri, 2005-09-30 at 07:39 -0400, Scott R. Burns wrote: > >> Hi Chuck, > >>Sorry I don't have any experience without a changer. You would be > >> best to ask the list about this one. There may be a way to have it > >> pause and prompt for the next tape ? > >> > >> I do know that you can pick up the changer I have on Ebay usually for > >> about $ 100 USD - $ 200 USD with a 30day warrenty. Unfortunately I > >> bought mine brand new in it's day for about $ 3000 USD :-( > >> > >> Scott... > >> > >> Scott R. Burns > >> NETCON Technologies Incorporated > >> Suite 135 - 4474 Blakie Road > >> London, Ontario, Canada > >> N6L 1G7 > >> Voice: +1.519.652.0401 > >> Fax: +1.519.652.9275 > >> Web: www.netcontech.com > >> > >> -Original Message- > >> From: Chuck Amadi Systems Administrator [mailto:[EMAIL PROTECTED] > >> Sent: Friday, September 30, 2005 6:23 AM > >> To: Scott R. Burns > >> Subject: RE: My Monthly archive config - issue > >> > >> > >> Hi > >> > >> I have received an error after running amcheck Monthly > >> > >> WARNING: if a tape changer is not available, runtapes must be set to 1 > >> > >> Thus I have not got a tape changer > >> > >> I just want to amflush data that cannot fit on tape 1 to 2,3 or in the > >> future tape 4 to backup potential around 80GB. > >> > >> Cheers > >> > >> Chuck > >> > >> On Thu, 2005-09-29 at 12:23 -0400, Scott R. Burns wrote: > >> > I have a similar setup. I have HW compression turned off on the > >> > drive (HP DAT24X6 changer). > >> > > >> > In my monthly config: > >> > > >> > > >> > dumpcycle 0 weeks > >> > runspercycle 1 > >> > tapecycle 1000 tapes > >> > runtapes 3 > >> > > >> > Also, record is turned off so my normal daily amanda config does not > >> > think the level 0 has been completed after the monthly. > >> > > >> > We never re-use our monthly tapes we send them offsite and leave > >> > them so thats why I have it set to 1000. We use between 2-3 tapes on > >> > a monthly run so runtapes is at 3. > >> > > >> > Scott... > >> > > >> > Scott R. Burns > >> > NETCON Technologies Incorporated > >> > Suite 135 - 4474 Blakie Road > >> > London, Ontario, Canada > >> > N6L 1G7 > >> > Voice: +1.519.652.0401 > >> > Fax: +1.519.652.9275 > >> > Web: www.netcontech.com > >> > > >> > -Original Message- > >> > From: [EMAIL PROTECTED] > >> > [mailto:[EMAIL PROTECTED] Behalf Of Chuck Amadi > >> > S
RE: My Monthly archive config - issue (Trying to source and use a tape changer if possible)
Hi all and Scott I am trying a Monthly archive but in order to follow a setup similar to Scott I need a tape changer. I have found a SCSI tape drive spec below it was once used for backups prior to moving over to Amanda. External Seagate DAT subsystem for NT, Windows, NetWare, DDS-3 recording format, consists of STD124000N DAT drive (data transfer rate 2.2 MB/s, 24 GB capacity with DDS-DC data compression), tabletop enclosure, tape, 1 m cable with 50pin high density plug, Thus could this possible be used a a tape changer I have checked the Amanda homepage but doesn't mention any devices. Cheers Chuck On Fri, 2005-09-30 at 07:39 -0400, Scott R. Burns wrote: > Hi Chuck, > Sorry I don't have any experience without a changer. You would be best > to > ask the list about this one. There may be a way to have it pause and prompt > for the next tape ? > > I do know that you can pick up the changer I have on Ebay usually for about > $ 100 USD - $ 200 USD with a 30day warrenty. Unfortunately I bought mine > brand new in it's day for about $ 3000 USD :-( > > Scott... > > Scott R. Burns > NETCON Technologies Incorporated > Suite 135 - 4474 Blakie Road > London, Ontario, Canada > N6L 1G7 > Voice: +1.519.652.0401 > Fax: +1.519.652.9275 > Web: www.netcontech.com > > -Original Message- > From: Chuck Amadi Systems Administrator [mailto:[EMAIL PROTECTED] > Sent: Friday, September 30, 2005 6:23 AM > To: Scott R. Burns > Subject: RE: My Monthly archive config - issue > > > Hi > > I have received an error after running amcheck Monthly > > WARNING: if a tape changer is not available, runtapes must be set to 1 > > Thus I have not got a tape changer > > I just want to amflush data that cannot fit on tape 1 to 2,3 or in the > future tape 4 to backup potential around 80GB. > > Cheers > > Chuck > > > On Thu, 2005-09-29 at 12:23 -0400, Scott R. Burns wrote: > > I have a similar setup. I have HW compression turned off on the drive (HP > > DAT24X6 changer). > > > > In my monthly config: > > > > > > dumpcycle 0 weeks > > runspercycle 1 > > tapecycle 1000 tapes > > runtapes 3 > > > > Also, record is turned off so my normal daily amanda config does not think > > the level 0 has been completed after the monthly. > > > > We never re-use our monthly tapes we send them offsite and leave them so > > thats why I have it set to 1000. We use between 2-3 tapes on a monthly run > > so runtapes is at 3. > > > > Scott... > > > > Scott R. Burns > > NETCON Technologies Incorporated > > Suite 135 - 4474 Blakie Road > > London, Ontario, Canada > > N6L 1G7 > > Voice: +1.519.652.0401 > > Fax: +1.519.652.9275 > > Web: www.netcontech.com > > > > -Original Message- > > From: [EMAIL PROTECTED] > > [mailto:[EMAIL PROTECTED] Behalf Of Chuck Amadi Systems > > Administrator > > Sent: Thursday, September 29, 2005 12:01 PM > > To: Amanda List > > Subject: My Monthly archive config - issue > > > > > > Hi again > > > > Its that time for a monthly archive backup I have currently 80GB server > > and using a DAT DDS-4 20GB native 40GB compression I am aware that I > > cannot have both hardware compression and software compression on So > > Amanda usually behaviour is to have hardware compression turned off > > using the mt command. > > > > Thus my amanda.conf is as follows > > > > I want a full dump for archiving and this tape will pulled out. > > dumpcycle 4 weeks # the number of days in the normal dump cycle > > runspercycle 2 # the number of amdump runs in dumpcycle days > > # (4 weeks * 5 amdump runs per week -- just > > weekdays) > > tapecycle 12 tapes # the number of tapes in rotation to pull each > > monthly tape for archiving. > > > > runtapes 1 # number of tapes to be used in a normal run. > > > > Should I increase runtapes to 2 to ensure that I backup at a minimum > > 40GB. > > Also should I amend dumpcycle to dumpcycle 0 weeks for a full dump and > > not incremental. > > > > Please advice of the best setup to backup for a monthly archive. > > > > Cheers > > > > > > > > > > -- > > Unix/ Linux Systems Administrator > > Chuck Amadi > > The Surgical Material Testing Laboratory (SMTL), > > Princess of Wales Hospital > > Coity Road > > Bridgend, > > United Kingdom, CF31 1RQ. > > Email chuck.smtl.co.uk > > Tel: +44 1656 752820 > > Fax: +44 1656 752830 > > > > > > > > > -- > Unix/ Linux Systems Administrator > Chuck Amadi > The Surgical Material Testing Laboratory (SMTL), > Princess of Wales Hospital > Coity Road > Bridgend, > United Kingdom, CF31 1RQ. > Email chuck.smtl.co.uk > Tel: +44 1656 752820 > Fax: +44 1656 752830 > > > > -- Unix/ Linux Systems Administrator Chuck Amadi The Surgical Material Testing Laboratory (SMTL), Princess of Wales Hospital Coity Road Bridgend, United Kingdom, CF31 1RQ. Email chuck.smtl.co.uk Tel: +44 1656 752820 Fax: +44 1656 752830
