DDMGR(8)DDMGR(8)NAMEddmgr - Device detection manager. Manages auto-detection on local and
remote storage nodes.
SYNOPSISddmgr [ -S ] [ -M ] [ -q ] [ -v ]
DESCRIPTIONddmgr is the main daemon for auto-detection that runs on the NetWorker
server machine. It spawns child processes (of dvdetect) for each stor‐
age node on which devices are to be detected.
It starts the child processes with the help of the nsrmon(8) process,
and depends on nsrmon to report on the success or failure of the remote
dvdetect process.
Once dvdetect on a storage node has finished its work of detecting
devices, ddmgr takes up the task of creating resources for these
detected devices, and in case of jukeboxes, tries to find out the
device mapping (element id to device path) by spawning another process,
dtbind. dtbind determines the device mapping by loading each drive in
the jukebox that was detected and then trying to access it via various
device paths till it finds the right one. This might take a long time
depending on the type of the jukebox.
ddmgr is invoked by the nsrd process and is not be invoked on the com‐
mand-line.
OPTIONS-q Tells ddmgr to detect and create device resources but not to
enable them.
-M This option tells ddmgr that it has been invoked by the server
and to direct messages to the daemon log.
-q This option tells ddmgr to run in the 'quiet' mode without
printing any messages.
-v This option is used to run ddmgr in the verbose mode for more
debug messages.
EXIT STATUS
Exits with 0 on success and 1 on error. See error messages for more
detail on errors.
SEE ALSOnsrmon(8)DIAGNOSTICS
Most, if not all, of ddmgr error reports is preceded by the phrase
"Detection process for host X reports", followed by the actual error
message. This error message is based on the error reported by the nsr‐
mon process monitoring the dvdetect process, or in cases where nsrmon
itself cannot be started, about the nsrmon process. The following are
the error messages that ddmgr might produce along with their implica‐
tions and possible solutions.
remote dvdetect exec failure. Errno 76
The remote storage node was unable to start the dvdetect process
on the remote storage node. This could happen for various rea‐
sons, like the dvdetect binary not having execute permissions,
or more commonly, the remote storage node not being configured
to service requests from this server.
remote auto-detect feature not supported
Auto-detect was being performed on a host that does not support
this feature. The client/storage-node should be 6.x or higher.
dvdetect process failed on signal
The remote dvdetect process was killed by a signal. This could
happen even when the process encounters a memory fault. Check
for core files in the nsr/cores directory.
dvdetect terminated due to timeout
The dvdetect process was terminated because of its inactivity
for a certain period of time. The timeout is set by default to
15 minutes. This is not user configurable. dvdetect process
exited on signal The local dvdetect process was killed by a sig‐
nal. This could happen even when the process encounters a memory
fault. Check for core files in the nsr/cores directory.
dvdetect exec failure
The ddmgr process was unable to start the dvdetect process on
the server. Check for execute permissions on the dvdetect
binary.
nsrmon exec failure
The ddmgr process was unable to start the nsrmon process on the
server. Check for execute permissions on the nsrmon binary.
nsrmon process exited on signal
The nsrmon process exited on a signal. This could even happen
when the process encounters a memory fault. Check the nsr/cores
directory for a core file.
dvdetect failed with unknown error
ddmgr was unable to determine the cause of the failure of the
dvdetect process.
nsrmon failed. No info in the resdb
The nsrmon process exited without loggin any information about
either the remote dvdetect process or itself. Ddmgr is unable to
verify status of both.
nsrmon failed. Invalid request or hostname
The nsrmon process was started with an invalid option or host‐
name. Check if the remote storage node is reachable from the
server.
nsrmon failed. Authorization failure
The nsrmon process could not get authorization from the Net‐
Worker server to talk to the remote storage node.
nsrmon exited on resdb access failure
The nsrmon process encountered errors in reading the NetWorker
RAP database.
nsrmon exited on memory failure
The nsrmon process ran out of physical memory while processing.
Add more memory.
nsrmon failed. Invalid request value
The nsrmon process was asked to perform a request it is not
familiar with.
process exited with error
There was a problem with the detection process but ddmgr could
not determine the exact cause of the failure.
RPC error Remote systems
The nsrmon process was unable to connect to the remote host.
This could be because of network problems, or if the NetWorker
processes were not installed on the remote system.
