[Hampshire] Tape drives - one can't read from t'other!
Hi all At my wits end with this so hopefully someone with more experience can help Does anyone know why a tape written on a given drive will not be readable on another drive when theyre the same format and being written / read with the same method? Ive written a series of backup tapes (I know this is archaic technology but I want write-once-read-many and I want something non-volatile hence tape). Ive bought 2 drives: one SAS based which is doing the writing and, mindful this is old technology, another SCSI based. The two drives are installed in separate boxes. FWIW the working SAS box is running jammy and the (apparently) working SCSI box is running noble though I suspect this makes little difference. Trouble is: the SCSI drive is flaky / mostly non-working reading only tapes written by the SAS drive. I happen to have some pre-used tapes which were written on a completely different drive (i.e. neither of mine made them) and the SCSI drive can read them fine. Therefore, the SCSI drive, HBA and cable are all fine. For some reason, it just cant read the tapes Ive just written on the SAS box. And yes the SAS drive can read back the tapes it has just written itself. So why would a LTO4 SCSI drive not be able to read from a LTO4 SAS drive when it can read LTO4 tapes written on another machine? FWIW the write command Im using is: tar czvf /dev/nst0 files_to_write For reading, I use: dd if=/dev/nst0 bs=1M | tar xzvf Both The read command works fine on the SAS drive to read its recordings back (so I know the recording has worked) but if I take one such tape (written on the SAS drive) and try to read it using the same command on the SCSI drive no dice all I get is Input / Output error. Things Ive tried: 1. A cleaning tape seemed to go through its paces but no change 2. Testing for it being a tar issue, I tried: dd if=/dev/nst0 bs=1M of=fred.img After a long period of tape activity, I get Input / Output error and fred.img is 0 bytes long. So in short, it looks like both drives are working fine but the SCSI one cant read tapes written on the SAS one but can read tapes written on other drives. FWIW the SCSI drive can read its own tapes. Any constructive advice very welcome. With 20Tb SSDs being so pricey, HDDs being mechanical, Cloud storage for 20Tb being laughably expensive tape is all I can think of for an archive format. And, of course, newer LTO protocols are, again, beyond my price range. I believe were up to LTO9 now but thats ~£2k for the drive itself even if it would mean far fewer tapes. Cheers R -- Please post to: Hampshire@mailman.lug.org.uk Manage subscription: https://mailman.lug.org.uk/mailman/listinfo/hampshire LUG website: http://www.hantslug.org.uk --
Re: [Hampshire] SMPT Authentification Methods for Hotmail
Looks like we are heading to a happy ending. I did spend some time looking at updating the code but it was looking very complex especially since I have so little time. However it looked like an interesting thing to do but not under pressure. I managed to find a work around that keeps the invoices flowing albeit at the cost of an extra hour per week so the pressure is off. It looks like Adams suggestion of Mythic beasts is the better solution. As a bonus, the company had a mish mash of providers, domains and emails that had grown uncontrolled over the years and the staff had been crying out for consolidation and it looks like this is going to happen. As for the warm feeling, it is always nice when strangers help out when you are not sure what to do. Back in the day this list could have 2 or 3 queries a day and the amount of time saved must have been significant. So once again, Thank you all for your help. Roger On 02/10/2024 16:28, Brad Rogers via Hampshire wrote: On Wed, 2 Oct 2024 16:13:48 +0100 Roger Munford via Hampshire wrote: Hello Roger, Thank you all for your help and advice. YW, Roger. After all these years it gives me a warm feeling. Oh dear. That bad, eh? :-) I will let you know what happens. I look forward to hearing about it. I'm not an Oauth user myself, but you never know; one day. -- Please post to: Hampshire@mailman.lug.org.uk Manage subscription: https://mailman.lug.org.uk/mailman/listinfo/hampshire LUG website: http://www.hantslug.org.uk --
Re: [Hampshire] Tape drives - one can't read from t'other!
One of the common issue I had back when doing tape backup was head alignment, it only had to be a fraction out and then you had the situation you have now. I know some drive did have a slight bit of alignment option but not knowing it it up or down left or right it would be a bit of trial and error (even slackening the securing screws and retightening the screw might be enough. The other point to check is how clean is the head, it might need a clean. Tim H On 04/10/2024 12:06, rmluglist2--- via Hampshire wrote: Hi all At my wit’s end with this so hopefully someone with more experience can help… Does anyone know why a tape written on a given drive will not be readable on another drive when they’re the same format and being written / read with the same method? I’ve written a series of backup tapes (I know this is archaic technology but I want write-once-read-many and I want something non-volatile – hence tape). I’ve bought 2 drives: one SAS based which is doing the writing and, mindful this is old technology, another SCSI based. The two drives are installed in separate boxes. FWIW the working SAS box is running jammy and the (apparently) working SCSI box is running noble though I suspect this makes little difference. Trouble is: the SCSI drive is flaky / mostly non-working reading only tapes written by the SAS drive. I happen to have some pre-used tapes which were written on a completely different drive (i.e. neither of mine made them) and the SCSI drive can read them fine. Therefore, the SCSI drive, HBA and cable are all fine. For some reason, it just can’t read the tapes I’ve just written on the SAS box. And yes – the SAS drive can read back the tapes it has just written itself. So why would a LTO4 SCSI drive not be able to read from a LTO4 SAS drive when it can read LTO4 tapes written on another machine? FWIW the write command I’m using is: tar czvf /dev/nst0 files_to_write For reading, I use: dd if=/dev/nst0 bs=1M | tar xzvf – Both The read command works fine on the SAS drive to read its recordings back (so I know the recording has worked) but if I take one such tape (written on the SAS drive) and try to read it using the same command on the SCSI drive – no dice – all I get is “Input / Output” error. Things I’ve tried: 1. A cleaning tape – seemed to go through its paces but no change 2. Testing for it being a tar issue, I tried: dd if=/dev/nst0 bs=1M of=fred.img After a long period of tape activity, I get “Input / Output error” and fred.img is 0 bytes long. So in short, it looks like both drives are working fine but the SCSI one can’t read tapes written on the SAS one – but can read tapes written on other drives. FWIW the SCSI drive can read its own tapes. Any constructive advice very welcome. With 20Tb SSDs being so pricey, HDDs being mechanical, Cloud storage for 20Tb being laughably expensive – tape is all I can think of for an archive format. And, of course, newer LTO protocols are, again, beyond my price range. I believe we’re up to LTO9 now – but that’s ~£2k for the drive itself even if it would mean far fewer tapes. Cheers R -- Please post to: Hampshire@mailman.lug.org.uk Manage subscription: https://mailman.lug.org.uk/mailman/listinfo/hampshire LUG website: http://www.hantslug.org.uk --
Re: [Hampshire] Tape drives - one can't read from t'other!
On Fri, 4 Oct 2024 at 17:01, Tim via Hampshire wrote: > > One of the common issue I had back when doing tape backup was head alignment, > it only had to be a fraction out and then you had the situation you have now. > I know some drive did have a slight bit of alignment option but not knowing > it it up or down left or right it would be a bit of trial and error (even > slackening the securing screws and retightening the screw might be enough. > The other point to check is how clean is the head, it might need a clean. > I would suspect the tape head alignment also. Back in the day, we just got the tape backup devices serviced / calibrated / aligned at regular intervals. I don't know what the service engineer did but it kept them working well. It was a good choice you made, to get two devices, otherwise you would never have found out that you had a problem. Keep in mind that tape media deteriorates over time, so make new duplicates over time. Kind Regards James -- Please post to: Hampshire@mailman.lug.org.uk Manage subscription: https://mailman.lug.org.uk/mailman/listinfo/hampshire LUG website: http://www.hantslug.org.uk --
Re: [Hampshire] SMPT Authentification Methods for Hotmail
On Fri, 4 Oct 2024 12:23:01 +0100
Roger Munford wrote:
Hello Roger,
>As a bonus, the company had a mish mash of providers, domains and
>emails that had grown uncontrolled over the years and the staff had
>been crying out for consolidation and it looks like this is going to
Often, I decry consolidation (I keep email separate from ISP, web
hosting, etc.). However, there are circumstances where it makes sense.
>As for the warm feeling, it is always nice when strangers help out when
Agreed. When parts of the world seem set on annihilating each other,
small acts of kindness can go a long way to restoring one's faith in
humanity.
>Thank you all for your help.
Glad it's all working out for the best.
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