What is the Advantages/Difference between using a Backup software (NBU) or a library to clean the tape drive

[Anth105]

Hi

I am looking for useful documents that describe or outline the Advantages/Difference between using a Backup software (NBU) or a library to clean the tape drive.

My Netbackup 6.5 env is connected to an IBM TS5300 that have "automatic tape drive cleaning enabled" but for the past 3 mths the drives keep going "down" randomly.
I have carried out all the usual HW troubleshooting steps ( fibre connections, reset drive path, reboot the library, persistent binding,  IBM  Engineer on site visit , etc ...) without much sauces.  The last IBM engineer to investigate the issue, advised me that this problem has been going on for nearly 2yrs ( I have been there for nearly 3 and 1/2 mths). He also mentioned that this downing drive  is  linked to the fact the library does not always unload the cleaning tape properly.  For some unknown reasons the tape is stuck into the robot.

after gathering all the evidence, I have decided to set up automatic tape cleaning in NBU to see if this can alleviate/resolve the issue.  But before going ahead with it, I wonder if someone can help me to find some good literature on the above subject in order to persuade the management why it would be beneficial for us to to try the NBU route.

Much appreciate your help  in advance

PS:  I am not after how to set automatic tape cleaning in NBU docs.

thanks

Anth105
 

[V_Dinesh]

hi,

The main advantage i feel is , you are working with netbackup admin console and you will be getting a job triggered on the master server for automated cleaning jobs cofigured by NBU.

If the cleaning job triggered u ll be notified and also if its failed u ll get the status in the activity monitor.

Where as in the hardware level cleaning u ll not get any notification.

Correct me if am wrong....

Thanks
Dinesh

[mph999]

Dinesh makes a good point re. the cleaning tape job status being available in NBU.

My preference is to let the library take care of it, why - well, it's one less step of complexity.  If the library an do it, then why involve NBU.

However, I appreciate in your case this isn't working.

To answer your question ...

" ... before going ahead with it, I wonder if someone can help me to find some good literature on the above subject in order to persuade the management why it would be beneficial for us to to try the NBU route. "

Not being funny here - the library isn't working, IBM have failed to resolve the issue, so you need to see if NBU can make it work - there is your justification.  However, if the issue is definately with the cleaning tape not being loaded/ unloaded correctly, then I don't see how getting NBU to do it will make a difference.

Martin

[Deepak_W]

let it be taken care by NBU as

1. master server has control over the TL anyways
2. if you can manage TL from NBU then why to manage two consoles and load oneself
3. you can schedule the TL cleaning from NBU console. so that means it is automated as well.
for eg - clean TL after evry 250 jobs.

By this you don have to look into when to run the job and when not...


Also you get cleaning job logs (success / failure), it if is failed by some change you'll get the notification. After that anyways you can login to the TL console and clean the TL manually.

Note- I haven't seen such jobs faling as far as you have cleaning media in it.

hope this mean a clarification for you...

[Sriram]

In My setup i have let library to manage the cleaning with no issues till now.  Same library

You said when the cleaning was managed by library it didn't ejected the tape back and the drive was down.  In this case if NBU is going to manage the cleaning, logically speaking it will also fail because the drive has some other issue as it is going down.

If you have the support contract for the library still, then ask the service engineer to replace the drive and check if the firmware version for the library and the drive is up to date.

This should definetely resolve your issue.

[Will_Restore]

Not a sticky situation then.   :)

I agree with Sriram - have them swap out the drive. 
The engineer knows this has been going on for almost two years?  :(

[J_H_Is_gone]

I have an IBM TS3310 and I let the library do the cleaning.
When a tape drive ask for a cleaning the library will clean it. 
My library is set up to send me emails if it has issues like the cleaning tape is used up or in your case got stuck.
I don't like letting NB do the cleaning as NB can as for a cleaning for a bunch of different reasons - not just because the tape drive as for it.  And this causes the drive to get cleaned too much some times.  Which then wares our the drive heads.

My thought on the cleaning tape getting stuck, have you tried changing out the cleaning tape for a new one.  As this one might have a broken leader or is not seating correctly inside the cartridge.

[mph999]

"I don't like letting NB do the cleaning as NB can as for a cleaning for a bunch of different reasons" ...

It shouldn't do.  Don'r ever set frequency based cleaning though, else, yes, it will either over or under clean.

When using NBU for cleaning,  NBU will activate a clean when it detects the tapealert sent from the drive, so in fact, the tape drive starts the process off.

The only difference between the library cleaning and NBU cleaning is who requests  to load the tape.

Library clean :

The tapealert from the drive cause the library firmaware to load the tape.

NBU clean:

The tapealert from the drive is ignored by the library, NBU detects this tapealert and asks the library to load the tape.

It's persoanl preference, Deepak likes NBU to clean, I think why bother, and like the library to clean.  However, I strongly disagree about cleaning after a set time, eg 250 jobs, why, the drive knows when it wants to be cleaned, extra cleans "just to be sure" will shorten the life of the drive.  It may be, that after a bad tape is used, the drive needs a clean after 5 uses - you cannot say, only the drive itself knows when to clean.

Martin

[Stumpr2]

I agree with Martin.
An issue that prompts a tapealert may not mean that the heads need to be cleaned.
I prefer to monitor, troubleshoot, and clean the tape drive manually if necessary.
That is my preference but I understand that this procedure is not always available.
The number of drives and access to the library and drives may dictate autocleaning.
If auto cleaning is required then I would opt to having the library take care of it.

[Ron_Cohn]

Environment:

NBU 6.0 MP5 for Windows

If you have a cleaning slot defined within a tape library AND tape alerts is active (which it is by default), I know when using NBU Vault, after *every* image the physical tape is unloaded and reloaded.  Just pull up a chair with a 6 pack and pretzels and enjoy the show.

This is behavior that has been recreated by several members of this forum in the past.  Once barcode rules have been defined and the slot defined as a data slot instead of a cleaning slot, the above mentioned behaviour stopped.

[George_Bowen]

I pretty much let the library issue the commands for cleaning the drives.  The library knows when you the heads need cleaning.  Let it handle that part.  Give it something else to do & make it feel "loved."