How to use LTO6 and LTO8 Drives simultaneously

[MatBams]

Hi,

We bought 4 LTO8 drives and we have 4 LTO6 drives in our robotic Oracle SL3000.

We need to affect LTO8 drives for server backups and LTO6 drives for NDMP.

I understand that it's impossible to determine what drive to use in SU.

If i define LTO6 tapes in HCART2 and LTO8 tapes in HCART3, is it okay ?

Thanks for your help.

[quebek]

Hello it is OK - just remember to have same type for tapes. So LTO8 hcart2 and LTO6 hcart3... you can even use DLT or 8mm or any other - up to you as long media type matches STU type ;)

So go for it.

[mph999 · Accepted solution]

The one exception is qcart - do not ever use this ...

All the other densities are just labels, hcart2 tape goes into an hcart2 drive etc ...   qcart is a special case and causes NBU to write in a fixed block size, which if you are not using qcart drives will cause failures.

[Nicolai · Accepted solution]

And use different barcode series for LTO6 & LTO8. Makes it a lot easier to manage and identify media

e.g:
A00000-A10000 LTO6
B00000-B10000 LTO8

[sdo]

@MatBams although you might not realise it yet, that post from @Nicolai is one of the best pieces of advice that you will ever receive (on this topic) - 'tis the voice of wisdom and experience.

[MatBams]

Thanks for your anwsers.

I've define my LTO8 drives as HCART2 and create a new SU of HCART2 just for LTO8 drives.

My question is how define the type of tapes when I insert new tapes without using a new barcode serie ? Because we bought 40 LTO8 tapes before integration of the LTO8 drives.

If i use a new barcode serie for LTO8 tapes, i have to create barcode rules in robot inventory to indicate where the tape goes in volume pool according to his type (HCART2/HCART3) ?

If i'm not clear, ask me !

[sdo · Accepted solution]

If you go with @Nicolai suggestion of "A" and "B" media, then here's how I might configure a new environment, but you might not need all of this, as it sounds like you already have some parts of this configured, so you'll have to pick out the bits that you do need, and/or modify accordingly as neccessary to suit your site specific needs :

vmpool -listall -b
vmpool -list_scratch
vmpool -add         ScratchPool "Scratch pool" ANYHOST -1 -2
vmpool -set_scratch ScratchPool
vmpool -listall -b

vmquery -list_media_genrule
vmquery  -add_media_genrule 0 8 "1:2:3:4:5:6"
vmquery -list_media_genrule

vmrule -listall -b
vmrule -verbose -add "A"    hcart3       ScratchPool  0 "LTO6 media"
vmrule -verbose -add "B"    hcart2       ScratchPool  0 "LTO8 media"
vmrule -verbose -add "CLNA" hcart3_clean None        25 "LTO6 cleaner"
vmrule -verbose -add "CLNB" hcart2_clean None        25 "LTO8 cleaner"
vmrule -listall -b

# ...inventory the robot and list media present in robot:
vmquery -b -rn 0
vmupdate   -rn 0 -rt tld -use_barcode_rules -use_seed
vmquery -b -rn 0

.

And the hcart "types" I use above are derived from... typically in the past, one would have expected to see hcart types like this :

LTO1 hcart
LTO2 hcart2
LTO3 hcart3
LTO4 hcart
LTO5 hcart2
LTO6 hcart3
LTO7 hcart
LTO8 hcart2
LTO9 hcart3

...i.e. one would not normally expect to find a library containing LTO drive types more than three generations apart.

[sdo]

Personally, I would modify my notional label sets to be something like :

A00000-A09999 LTO6
B00000-B09999 LTO8

...because then a rule of "A0" encompasses the first set, and a rule of "B0" encompasses the second set - i.e. do you see how A10000 actually belongs to a different set, because it begins with "A1".

[sdo]

As long as the new LTO8 media have not been used yet, then... if you have to delay implementation and purchase new labels - and also go to site to remove the old labels, and replace with new ones... then this is well worth the delay and effort - as your long life (that you have yet to experience) of media management will be so much easier going forward in the long term.

If it is a pain for management to experience a short delay, then chalk it up to experience.  Lesson learned.  Which is... always plan in detail your media types, and media labels / barcodes well in advance of purchase, and well in advance of implementation.

[MatBams]

I think that we'll do like this : Leave the barcode serie of LTO6 tapes. Modify the barcode of 3 LTO8 and the others in the pack with "B0" prefix and command new LTO8 tapes with the same barcode prefix.