NAME

nsrck − NetWorker index consistency check and repair program

SYNOPSIS

nsrck [ −q ] [ −X [ −x percent ] | −F ] [ clientname ... ]

DESCRIPTION

Nsrck is used to check the consistency of the NetWorker on-line index of clients’ save records.  Normally, nsrck is started automatically by the nsrd(8) program when it is invoked, and by nsrim(8) after it finishes checking the media database. 

Index consistency checking is done in two or three phases. 

Phase zero determines if any further checking of a client’s index is necessary.  The existence of the client’s db.SCAVENGE file indicates that further checking is required.  Phase zero also reports on any suspicious-looking index names (i.e.  indexes whose names cannot be mapped into network addresses). 

Phase one dumps all records from the damaged index db file to a new database file.  Typically the file is db.RECOVER.  However, if there is not enough room in the filesystem for both db and db.RECOVER, then a temporary file is created elsewhere and db.SCAVENGE is set to point to that temporary file.  The program prints (to standard error) alternate ‘−’ and ‘>’ characters as it makes progress in copying the records to the temporary file.  Once db is emptied, then it is removed.  If db.SCAVENGE was created, then its records are copied into db.RECOVER.  The program prints (to standard error) alternate ‘<’ and ‘=’ characters as it makes progress in reloading the index. 

Phase two moves db.RECOVER back to db and rebuilds internal indexes.  At the end of phase two, nsrck removes the db.SCAVENGE file. 

The nsrck program is restartable at any time during its execution.  Therefore, it can survive system crashes or exhaustion of resources without losing data. 

OPTIONS

−q Quiet mode.  All advisory messages are suppressed. 

−F [ clientname  ... ]
Force a check. Phase zero is overridden with the specified host names. Because nsrck creates new index files, the −F option may be useful for releasing unused index pages to the UNIX filesystem.  This is typically only necessary when the browse policy (see nsr_policy(5)) is reduced, e.g. changing the browse policy from 1 year to 6 months. 

−X [ clientname  ... ]
Do not check the index databases, rather cross-check the save set ids in the index records with save sets found in the media database.  Records that have no corresponding media save sets are discarded. If any clients are listed, the cross-check is limited to those indexes.

−x percent
After a database has been cross-checked, if the database uses less than percent of the UNIX file, then the database is forcibly checked in order to release unused pages back to the filesystem.  The percent default is 30. 

FILES

/nsr/tmp/.nsrck
Nsrck locks this file there by insuring that only one copy of the command thrashes the NetWorker server. 

/nsr/index/clientname

/nsr/index/clientname/db

/nsr/index/clientname/db.SCAVENGE

/nsr/index/clientname/db.RECOVER

SEE ALSO

nsr_layout(5), nsr_policy(5), nsrindexd(8), hosts(5), nsrim(8), saveindex(8)

DIAGNOSTICS

Checking clientname. 
Informative message that the files associated with the named client are being inspected.

Machine clientname is not in the host table. 
The name of the subdirectory being checked has no counterpart in the host table.  Therefore, the client index name is suspicious.

No disk space available (%d Kbytes) to check filename. 
The program cannot find enough disk space to hold the temporary file db.SCAVENGE.  The operator should free some disk space on any local filesystem and retry the command.  Alternatively, the operator may make the db.SCAVENGE file a symbolic link to a remote file whose filesystem has enough free space, and retry the command.  The df(8) command may be used to see how much free space is available on any filesystem. 

File name.SCAVENGE is locked!  Access denied!  Cannot open index file name. 
The named file is already in use by another instance of this program, or by the nsrindexd daemon.  Since disaster will ensue of two processes access the same index at the same time, the program will refuse to act on the named file.  Multiple access detection is implemented via an advisory file locking mechanism. 

−> Cursor motion which indicates that progress is being made in Phase one.  Many records are scavenged for each cursor state change. 

name: %d records scavenged, %d lost. 
The informational record printed at the end of Phase one. The lost count is typically zero. 

<= Cursor motion which indicates that progress is being made in Phase one.  Many records are recovered for each cursor state change. 

name: %d records recovered, %d discarded. 
The informational message printed at the end of Phase two. The discarded count should be zero. 

Building indexes for clientname. 
An informational message printed during phase two as various indexes are rebuilt.  Note that building an index takes approximately as long as phase one.

Expunging records from invalid save set time %d. 
Seen only with the −X option when cross referencing with the media database finds records that have no associated tape locations.  Such records are removed. 

nsrck is checking index for <client>
Displayed when the −F option is in effect, or when the client’s database had to be checked upon start up. 

nsrck is cross-checking index for <client>
Displayed when the −X option is in effect. 

nsrck is compressing index for <client>
Displayed when the −x option has taken effect. 

nsrck has completed (cross check)
Displayed as the program finishes, provided some form of checking was accomplished.

NetWorker 4.1.2  —  Last change: May 1995