Expiry Time for HPLTO4 Tapes

[abidghori]

Dear All,

I would like to the expiration time for Media Tapes(HP LTO4) and what is the maximum number of mounts should be ideal for a Tape.

Regards

agadmin

[Nicolai]

Source

http://www.tapeonline.com/faqs/maxell-lto-ultrium-4-data-cartridge#whats-the-archival-life-of-lto-4-...

What's the archival life of LTO 4 media?

Under optimum operating and storage conditions, Maxell LTO 4 media is expected to have an archival life of more than 30 years.

Operation Environment 

Ambient Temperature 50F to 113F (10C to 45C)

Relative Humidity 10% to 80%

Storage Environment (non-archival)

Temperature 61F to 95F (16C to 35C)

Relative Humidity 20% to 80%

Storage Environment (archival)

Temperature 61F to 77F (16C to 25C)

Relative Humidity 20% to 50%

How often should I replace my LTO 4 media?

Under optimum operating and storage conditions, Maxell LTO 4 media is expected to be able to perform 250 full back-ups. Maxell recommends replacement of the media once 250 full backups have been performed.

But keep in mind 250 full backups isn't the same as 250 mounts. Also you need to divide minimum retention with the expected media lifetime. In my case minimum retension is one month and I expect LTO4 to be in operation in 3-4 years. That makes a usage 3 years usage count of 36 or 48 for 4 years (that well below 250 full writes).

[abidghori]

Another question is how many times i should allow to mount like

Can i use regularly and mount exceeds 100 ?

Can i use the tapes for more than 3 years?

[Mark_Solutions]

In general the tapes should be good for 3 to 4 years and over 100 mounts

NetBackup will report to you any issues with tapes as bptm process detects the hex alert values received from the tape drives

The tape library itself should also alert you to any issues

There are lots of variables that have an effect on tape life and these are predominantly the handling and storage of the tapes as well as having an efficient (but not excessive) tape drive cleaning regime.

So we could say a tape is good for 4 years usage and 250 mounts but if handled well they could last much longer, handled poorly they will not last as long.

Also bear in mind that when looking at the number of mounts as a setting that a tape could be mounted multiple times in a single nights backups so 100 may not be very long!

The majority of my customers do not restrict their tape usage and leave the defaults - NetBackup will freeze a tape after three errors and in general the tape will still be readable when this occurs so the data is safe.

If you budget is no problem then by all means set restrictions but do not pin them down with too low a value

Hope this helps

[Nicolai]

The biggest threat to tapes are dust and manual handling and temperature changes (based on where in the world you live).

[Omar_Villa]

Mounting is not realy a problem, you can mount a tape 1000 times and if you dont read or write to it, will be fine is just a mount, the life time of the media is at the tape it self, passing to many time the reading and writing heads over the magnetic media is what degrades the tape life time, so to keep a better control of your medias life time you can split the tape headers by weekly, montly, yearly, so you know which ones you are using more. Netbackup doesnt have a good report on this but I'm sure it can be scripted.

[mph999]

It is an impossible question.

We can all give different answers and we can all be correct - you don't know the answer until the tape fails.

The ONLY way this can be accurately measured is via 3rd party software, such as storsentry.

http://www.hi-stor.com/site/index.php?pge=62

This is not connect to any backup vendor, it is a 3rd party solution, and it works very very well (I've used it).

As Nicolai pointed out, the limiting factor is not so much the number of mounts, more the total end to end passes of the tape - to fully write a LTO tape, it passed over the drive heads multiple times, the drives heads just move out slightly to read the next 'set' of tracks.

I had this exact conversation with one tape vendor (Imation) when we were facing some media issues (in my old job).  Speaking with their experts, we concluded, that for our environment, the number of mounts had no effect on tape reliability.

The second (or equal 1st) threat to LTO tapes is shoe shining.  Not only does this wear the tape (and drive)  very quickly, it untensions the tape pack which can cause edge damage when the tape  is manually moved.

So, step one to looking after tapes is to make sure you can backup to them above their minimum streaming speed.  In my experience, most people cannot do this.

Regards,

Martin