[Wylug-help] Tape drive advice

[Steven Dodd]

On 2005.01.25 14:10, James Holden wrote:
> Gary Stainburn wrote:
>
>> On Tuesday 25 Jan 2005 11:41 am, James Holden wrote:
>>
>>
>>> Gary Stainburn wrote:
>>>
>>>

>>
>> I'm looking at the SCSI ones but have had experience of controllers
>> not
>> working with Linux. I'm looking at the Adaptec AVA 2904 - Any
>> comments
>> anyone?
>>
> Dunno about that specific model, but my 2940 works nicely. My tape
> drive
> is on it.
>
I can report an Adaptec 2930 working fine with an HP DDS autochanger
under Suse 9.1.  Adaptec cards tend to be well supported, but double
check for their newest cards - I think Adaptec supplied drivers tend
to be binary only.

>>
>> The system I'm currently looking at is NTBackup to a Samba share,
>> then
>> backup that to tape, so I'm guessing there'll be no compression at
>> all
>> on the tape.
>>
>>
>>
If you're using any compression to create the NTBackup file, then turn
off hardware compression on the drive (depends on the type of drive,
but usually it dictated by which /dev/st* entry you use).  Double
compression may increase the amount of data you're copying to tape.

>>
>> I'm now looking at the Certance CDL432 which is a 6 tape auto-
>> loader.
>> http://www.pcwb.com/servlets/Catalogue?id=(400533)&shop=PCWBD
>>

Looks to meet your criteria well.

>> I'm hoping that from Linux I can select which tape(s) to back up to,
>> so
>> that I can have a weekly rotation without human intervention.  So
>> far
>> I've not had much success finding anything on doing this though.
>>
>>
>>
You need to consider how much data you can lose.  If there'd be no
damage to your business if you wiped out the last weeks data, then
take this approach.  Otherwise change tapes every day - then you'll
lose no more than 24hrs data.

> AFAIK, tape changing is part of the standard command set for SCSI
> tapes.
> Tape autoloaders have been around for years (and years).
>
There's generally a command which will drive the changer for you.
Suse 9 has a command "mtx" which is in the package mtx (not installed
by default).  This allows you move tapes from specific slots to the
drive or from slot to slot and so on.  The description for the mtx
package says it is for DDS autoloaders, but as James says the command
set is pretty standard so, it should work for any changer.

>>>
>>> Don't forget the cleaning tape.
>>>
And use it according to the cleaning schedule for the drive, don't
wait until you can't read your tapes back.  Which brings up another
bit of good practice.  Periodically restore the tapes back to make
sure they are readable.

>>> Store the tapes somewhere sensible - cool, dry, vertical, away from
>>> monitors and other sources of EMI. Preferably offsite. Don't put
>>> too
>>> much trust in a fire safe.
>>>
>>>
>>
>> So, putting them on the window ledge in my office isn't a good idea?
>>
>>
>>
> Probably not.
>
At the very least, take the tapes home with you.  You'd have to be
quite unlucky to have your home and place of work burn down - unless
you live at work...

		from,
			Steve.