NDMP attached drive does not come on line after NetVault restart
After a restart of NetVault services or a reboot of the NetVault system the NDMP attached drives show as offline. They do come on line if I check the drive manually.
In the binary log we see the following:
Error 2015/03/30 09:57:51 0 Media Netvault Command failed, re-initializing driver
Binary log subtext show the following:
SCSI :05224 16 0 95745 CMD STATUS 'CHECK CONDITION' 
SCSI :05224 17 0 95745 CMD SENSE KEY 'NOT READY '  - ASC 3a ASCQ 00
SCSI :05224 18 0 95745 CMD SENSE INFO 'MEDIUM NOT PRESENT'
SCSI :05224 20 0 95745 CMD RETURN VALUE 2
SCSI :05224 14 0 95746 CMD TEST UNIT READY [ 00 00 00 00 00 00 ]
CAMNDMP :05224 157 0 95746 CMD 00 00 00 00 00 00
If drive diagnostics are enabled on the filer using the following command we see “tape device 3c.0 has more than one I/O pending, but the device supports only one I/O at a time” reported in the filer messages file.
mt -t <tape driver> diag 1
mt -t rst1a diag 1
messages file extract:
Wed Apr 8 12:00:49 CEST [s1800stp202:tapemc.iopending.exceeded:info]: tape device 3c.0 has more than one I/O pending, but the device supports only one I/O at a time.
If NDMP debug is also enabled we see NDMP4_UNDEFINED_ERR reported in the NDMPD debug file.
Extract from debug file.
00000035.00088672 004cd52f Wed Apr 08 2015 12:00:49 +02:00 [kern_ndmpd:info:4205]  DEBUG: error=20 (NDMP4_UNDEFINED_ERR)
Tape library and drive do not support overlap commands
For NetVault 9.2 and below:
NetVault Device Management
Right click the library and select 'Modify'
From 'Configure' tab, right click the library and select 'Configure'
From the 'Configuration' tab, look for the option 'Do not overlap command arm and drive' and select it, which effectively disable the overlap command.
For NetVault 10.0 and above:
Open command line and cd to …/NetVault/bin directory.
Issue the following command this should allow access to the config of the library.
deviceconfig.exe -username <NetVault user> –password xxxxxx -librarymachine <NetVault name of machine library is attached too> -libraryname <"library name in quotes">
deviceconfig.exe -username default –password xxxxxx -librarymachine HYPER-V-SUPPORT -libraryname "HYPER-V-SUPPORT: 1-0.0.0 (QUANTUM PX500)"
Note: if netvault user has no password “-password” not required
The changer device menu should appear as below:
1) Configuration ...
2) NDMP Configuration ...
3) Entry/Exit Ports ...
4) Cleaning ...
5) Mixed Media ...
6) SCSI Configuration ...
Please select an item (1-6):
Select 1 and configuration will appear as below:
1) Device Serial Number - QP0828BDC00008
2) Can scan individual slots - ON
3) Does not need to be initialized - ON
4) Ignore not ready while using EE ports - ON
5) Cannot request barcodes - OFF
6) Cannot retrieve barcodes - OFF
7) Can lock door with command - ON
8) Needs to supply arm address to motion commands - OFF
9) Must return media to slot it was loaded from - OFF
10) Gets Spurious Media Change Notifications - OFF
11) Gets Spurious Mode Change Notifications - OFF
12) Shadow tape media is supported - OFF
13) Maximum number of shadow tapes in report - 512
14) Check move media command before actioning - OFF
15) Need command to open entry/exit port - OFF
16) Do not issue unload commands to drives - OFF
17) Must unload drive(s) to open door - OFF
18) Do not overlap commands to arm and drive - OFF
19) Return inactive media to slot delay [0 = never] (secs) - 30
20) Mark Unknown Media Blank - OFF
21) Do Not Scan Unknown Media - OFF
22) Entry / Exit Port Locks Arm - OFF
Please select an item (1-22):
Select “Do not overlap commands to arm and drive - OFF” in this case option 18
We should see the option change as below:
18) Do not overlap commands to arm and drive - ON
Then select “b” for back
Then select “s” to Save
On completion restart NetVault service.