When right clicking a DR4100 device and selecting STATUS in NVBU Device Management, the "Stream count (0 defunct)" field shows a value greater than zero.
Example: Stream count = 4 (0 defunct)
However the DR4100 device is IDLE and there are no backup or restore jobs running that target this DR4100.
In certain scenarios, jobs run to the DR4100 will hang in "Waiting for media" when there are no other jobs running or the maximum stream number (8 by default) has not been reached.
This is a defect raised in Bug 24139.
When backup jobs targeting the DR4x00 systems are unexpectedly aborted or killed, the open streams to the DR4x00 are kept open.
When a DR4x00 device is added to NetVault, the NetVault rascontroller process will create a stats.stnz file on the DR4x00 under /server/<NVBU_server_name/stats/.
This file is used to keep count of the open streams to the device and is normally updated by the rascontroller process upon successful termination of a job.
In the event a job unexpectedly dies the stats.stnz file update does not happen and for NetVault Media Manager process, the streams are still open.
While this issue appears to be benign, it may become problematic if it keeps happening without any actions taken to resolve it.
By default the DR4x00 have a maximum simultaneous streams of 8 (configurable).
If the issue is undetected and keeps happening, the available stream count will decrease until there are no more streams allowed to the DR4x00.
In such situation, jobs targeting the DR4x00 system will remain hung in the "Waiting for media" state with the "Device has too many streams" message returned.
Until Bug 24139 is addressed, the following simple workaround will help reset the stream count:
1) In the majority of the cases, restarting NetVault should reset the stream count. However, this is not always true.
Depending on the plugin that was used during the unexpected job failure, and how the plugin process exited, not all NVBU restarts may reset the count.
2) If restarting NVBU does not help, make sure no jobs are running that are targetting the DR4x00 device
3) In NVBU Device Management, right click the DR4x00 device and select REMOVE
4) In NVBU Device Management, re-add the DR4x00 device using the same LSU/container
This should force the recreation of the stats.tsnz file and reset the stream count to this device, allowing jobs to successully target the DR4x00. Removing and re-adding the device in NVBU does not impact the stored savesets in this device.
