topic Re: How to fail library robotics or purposely generate robotics error in HPE StoreEver Tape Storage

How to fail library robotics or purposely generate robotics error

shirsatviraj — Wed, 23 Nov 2016 05:50:46 GMT

I need to find some scenario inorder to fail the library robotics or generate some kind of error which will not allow to move the cartridge from source to destination.

Re: How to fail library robotics or purposely generate robotics error

Torsten. — Wed, 23 Nov 2016 07:11:51 GMT

what library model and why?

Re: How to fail library robotics or purposely generate robotics error

shirsatviraj — Wed, 23 Nov 2016 07:31:45 GMT

It may be any MSL6480 or ESL G3

i need to generate this error inorder to test how the application handle such situation

Re: How to fail library robotics or purposely generate robotics error

Torsten. — Wed, 23 Nov 2016 09:05:23 GMT

If the robotics fail for any reason, the library will finally go offline and wait for manual operation. The tapes in the drives will probably continue to write, but unable to unload or load tapes.

You can easily test this by open a door of the library, the robot will not move with an open door.

Re: How to fail library robotics or purposely generate robotics error

Curtis_Ballard — Wed, 23 Nov 2016 15:30:08 GMT

The most recent response isn't quite correct. We've worked to remove the cases that will cause a library to go "offline" and there are very few cases now where that will happen. Most of the time after a move failure or other mechanical error the library will still accept new commands and attempt to perform them. Usually it will run a series of calibration steps at the start of the next operation and then attempt the operation.

If you are trying to induce errors the easiest thing to do is to do is to interfere with a source storage slot so that the library can't get the tape. One way to do that is to open a magazine and put a narrow cardboard insert in the slot with a barcode on that insert. The library will read the barcode and think that there is a tape in the slot but the library won't be able to grab that "tape" to move it to a drive which will result in a move failure. That method allows you to create a failure that looks exactly like a real mechanical failure but you don't have to do anything that might damage the library.

Re: How to fail library robotics or purposely generate robotics error

shirsatviraj — Thu, 24 Nov 2016 09:12:43 GMT

Hey thanks for your input , really it helped me to understand the functionlaity

Re: How to fail library robotics or purposely generate robotics error

shirsatviraj — Thu, 24 Nov 2016 09:13:26 GMT

yes i agree with you but is there any other way to do the same ?

Re: How to fail library robotics or purposely generate robotics error

Torsten. — Thu, 24 Nov 2016 09:48:34 GMT

Curtis suggested a failed move, I suggested a totally failed robot.
Whats wrong, what else do you want?

Re: How to fail library robotics or purposely generate robotics error

Curtis_Ballard — Thu, 24 Nov 2016 18:04:26 GMT

Leaving a door open to simulate a failed library is a useful experiment. I suggested an alternate method because software applications often have special handling for the "door open" error message and have special handling for that case so it doesn't go through the normall error handling logic. Some customers open the library door to bulk load tapes so some applications detect the open door noticiation and wait for it to be closed.

Re: How to fail library robotics or purposely generate robotics error

Torsten. — Thu, 24 Nov 2016 22:07:05 GMT

the question is, what do you expect from the test? if a tape cannot be loaded, the job will fail. a minor move problem will be fixed by retry by the lib itself, a major problem will probably stop the robot completely. there is a endless list of possible reasons depending on library model. this is my experience after working 20 years with all hp and other tape and optical libraries.

from this point of view curties' suggestion is the most useful test to see how the software can handle this.