EMC Legato NetWorker Commands Reference

scanner

SYNOPSIS

       scanner [ options ] -B -S ssid [ -im ] device

       scanner [ options ] -i [ -S ssid ] [ -c client ] [ -N name ] device

       scanner [ options ] -m [ -S ssid ] device

       scanner [ options ] [ -S ssid ] [ -c client ] [ -N name ] device [
               command ]

       options: [ -npqv ] [ -f file ] [ -r record ] [ -s server ] [ -t type ]
                [ -b pool ]

       command: -x command [ arg ... ]

DESCRIPTION

       The  scanner  command  reads  NetWorker  media, such as backup tapes or
       disks, to confirm the contents of a volume, to extract a save set  from
       a  volume,  or  to rebuild the NetWorker online indexes.  As installed,
       only the super-user may run this command.  However, the command's modes
       can  be  modified  such  that  normal  users  may run the command while
       retaining root privileges; see nsr(1) for  more  details.   The  device
       must  always  be specified, and is usually one of the device names used
       by the NetWorker server.  For tape drives, it must be  the  name  of  a
       'no-rewind  on  close'  device.  For adv_file type device, read-write
       device name will be used when read-only device name is specified.

       When scanner is invoked with either no options or -v, the volume on the
       indicated  device  is  opened for reading, scanned, and a table of con-
       tents is generated.  The table of contents contains  information  about
       each save set found on the volume.  By default, one line of information
       is written to standard output for each save set  found  containing  the
       client  name,  save set name, save time, level, size, files, ssid and a
       flag.  The client name is the name of the system that created this save
       set.   The name is the label given to this save set by save(1), usually
       the path name of a file system.  The save time is the date and time the
       save set was created.  The level values are one-letter abbreviated ver-
       sions of full, incremental, levels 0 through 9,  or  blank  for  manual
       saves.   The  size  is  the number of bytes in the save set.  The files
       labeled by column provide the number of client files contained  in  the
       save  set.  The ssid (save set identifier) is an identifier used inter-
       nally to reference and locate this save set.  This same identifier  may
       be specified explicitly with the -S option to extract a particular save
       set.

       The table of contents is based  on  synchronization  (sometimes  called
       'note') chunks (see mm_data(5)) interspersed with the actual save set
       data.  There are four types of note chunks: Begin,  Continue,  Synchro-
       nize,  and End, symbolized by a flag of B, C, S or E respectively.  The
       Begin note is used to mark the start of a save set.  When  a  beginning
       chunk  is written, the save set size and number of files are not known.
       The Continue note is used to indicate that this save set started  on  a
              Specifies  which  pool the volume should belong to.  This option
              only applies for versions of NetWorker that  do  not  store  the
              pool  information  on  the media.  For these versions, you might
              need to specify the media pool the volume should  belong  to  if
              the  user does not want the volume to be a member of the Default
              pool.  For volumes where the pool information is stored  on  the
              media,  the  media must be relabeled (destroying all data on the
              media) to assign the media to a different pool.

       -B     When used in conjunction with the -S option,  the  save  set  id
              specified is flagged as that of a bootstrap.

       -c client
              Process  only  save  sets that come from the specified NetWorker
              client machine.  This option can be used multiple times  and  in
              conjunction  with  the -N option, but only in presence of the -i
              or -x option.

       -f file
              Starts the scan at the specific media file number.  This  option
              is  not  useful  on  media such as optical disks and file device
              types, for example.

       -i     Rebuilds both the media and the online  file  indexes  from  the
              volumes read.  If you specify a single save set with the -S ssid
              option, only entries for the specified save set  are  copied  to
              the  online file index.  Note that for version 6.0 and later, if
              you have the tape that contain the index backups that  go  along
              with  the  data  backups,  the recommended way of restoring your
              indexes is to run  scanner  -m  to  reload  the  media  database
              entries  for the index and data backups.  Once that is done, you
              should run nsrck -L7 -t date <clientname> to recover  the  index
              for  the client as of the time of the backups on the tape.  This
              will roll the index entries for that time back into  the  index.
              However, if you have tapes for which there are no index backups,
              then you will need to use the -i option to reconstruct the index
              entries.

       -m     Rebuild the media indexes for the volumes read. If you specify a
              single save set with the -S ssid option, only  entries  for  the
              specified  save  set are copied to the media index, the save set
              data will be written to standard output which may be  redirected
              as  needed.  The media database will not retain the "scanned-in"
              status. There is no longer a flag to show  that  status  in  the
              "ssflags"  field.   The  saveset gets a new browse and retention
              policy depending on the time that it  was  scanned  in  and  the
              clock starts ticking for the saveset.

       -n     Checks   all   media  without  rebuilding  the  media  or  index
              databases.  When used with the -i option, this  option  provides
              the  most complete media checking available, while not modifying
              the databases at all.

       -N name
              Only processes save sets specified by  name  (a  literal  string
              only).   This  option can be used multiple times and in conjunc-
              tion with the -c option, but only in presence of the  -i  or  -x
              option.

       -s server
              Specifies the controlling server when using scanner on a storage
              node. See nsr_storage_node(5) for additional detail  on  storage
              nodes.

       -S ssid
              Extracts the specified save set(s).  When used with the -i or -x
              option, this option can be used multiple times and is  in  addi-
              tion  to  any  save  sets  selected using the -c and -N options.
              Otherwise, the volume is scanned for save set ssid,  which  will
              be  written to the standard output.  Most often this is piped to
              a uasm(1) program running in recover mode to  process  the  save
              set  (potentially with a directory list to limit the files to be
              recovered and potentially using a -m argument to  map  the  file
              location).   When using -S without -i or -m, scanner prompts for
              the volume block size if the volume label is not  readable.   If
              the  volume information is still in the media database, the user
              has the option of running recover by save set (see  recover(1)).
              When  -B  is also specified, ssid is taken to be that of a boot-
              strap.  Only one ssid is allowed in this case.

       -t type
              Specifies the type of media, for example, optical for an optical
              disk,  or 8mm 5GB for an 8mm 5GB tape).  Normally the media type
              is obtained from the NetWorker server,  if  a  known  device  is
              being used (see nsr_device(5)).

       -v     Displays  more  verbose  messages,  such  as  a log of each note
              chunk, and a message after every 100 media records. When the  -i
              option  is  used,  a  line  is printed  for each client file (an
              enormous amount of output can be produced).

       -x command arg ...
              Specifies an arbitrary UNIX command to process each new selected
              save  set.   This argument can only occur once at the end of the
              argument list (after device).  The save stream for each save set
              is  connected  to  the  stdin  of a new instance of the command.
              Most often this command is uasm(1) running in  recover  mode  to
              process  each  save  set (potentially using a -m argument to map
              the file location).  If the volume information is still  in  the
              media  database,  the  user has the option of running recover by
              save set (see recover(1)).  Do not attempt console I/O by speci-
              fied  UNIX command.  Instead specify conflict resolution parame-
              ters as arguments passed to the command (e.g.: scanner -S <ssid>
              -x  uasm  -iR  -rv).   If  console interaction is required, pipe
              scanner output to the desired Unix command instead  of  invoking
              the command using the -x option.

EXAMPLES

       Verifying a tape:

              scanner /dev/nrst0

       scanner: scanning 8mm tape mars.001 on /dev/nrst0

       client name   save set   save time  level        size   files    ssid S
       space         /export    10/07/94 12:38 f   100762460   10035   16983 E
       space         /usr       10/07/94 13:14 f    27185116    3185   16984 E
       scanner: scanning 4mm tape monday.fulls on /dev/nrst8
       scanner: ssid 17458697: scan complete
       scanner: ssid 17458694: scan complete
       scanner: ssid 17458698: scan complete
       scanner: ssid 17458693:  NOT complete
       scanner: reached end of 4mm tape  monday.fulls

       scanner: when next tape is ready, enter device name [/dev/nrst8]?

              nsrck -L7 -t  "06/07/99" supernova

       nsrck: checking index for 'supernova'
       nsrck: The file index for client 'supernova' will be recovered.
       nsrck: Recovering index savesets of 'supernova' from 'quasar'
       Recover completion time: Fri Jun 16 14:03:16 2000
       nsrck: completed recovery of index for client 'supernova'

       nsrck: /disk1/nsr/index/supernova contains 85782 records occupying 14 MB
       nsrck: Completed checking 1 client(s)

       Extracting a save set for /usr and relocating to /mnt:

              scanner -S 637475597 /dev/nrst8 | uasm -rv -m /usr=/mnt
                                                                   or
              scanner -S 637475597 /dev/nrst8 -x uasm -rv -m /usr=/mnt

       Extracting all save sets from client mars and relocating to /a:

              scanner -c mars /dev/nrst8 -x uasm -rv -m/=/a

SEE ALSO

       mm_data(5), mminfo(1), nsrmmdbasm(1), nsr(1), nsrck(1), nsrindexasm(1),
       nsrmmd(1), nsr_device(5), nsr_storage_node(5), uasm(1).

DIAGNOSTICS

       xdr conversion error, fn %d, rn %d, chunk %d out of %d
       unexpected file number, wanted %d got %d
       unexpected record number, wanted %d got %d
              All three preceding messages  are  indicative  of  media  errors
              (tape blocks are either lost or damaged).  In the case of an xdr
              conversion error, a non-zero 'chunk'  number  means  that  the
              block may be partially salvageable.  Unexpected file numbers are
              normal when scanner reaches the logical end of  the  media  that
              has been recycled.

       continuation of data in nsrscan.NNNNN.MMMMMM
              After  an  XDR  decode error (an error denoted by one or more of
              the messages described above), scanner attempts  to  re-synchro-
              nize and send the rest of the stream.  However, because programs
              like uasm(1) are unable to handle decoding  streams  with  parts
              missing in the middle, scanner sends the remainder of the stream
              to a file.  You can decode this stream manually.   For  example,
              if your original command was:
                   scanner -S ssid | uasm -r
              and  a  synchronization error occurs, you can decode the rest of
              the stream with the following command:
                   uasm -r < nsrscan.NNNNN.MMMMMM
              where the file name you enter corresponds to the name printed in

       ssid %d: finished, but incomplete
              Scanner has detected the end of a save stream,  but  the  stream
              was  aborted,  and  is  of dubious value.  If online indexes are
              being rebuilt, the end of the aborted stream may precipitate the
              next message.

       (ssid %d): error decoding save stream
              As indexes are being rebuilt, scanner detected that the bytes in
              the save stream are invalid.  This is usually caused by process-
              ing  an aborted save stream.  Other causes may include a damaged
              tape.   Once  this  condition  is  detected,  the   process   of
              rebuilding  the  indexes  for  the particular save stream exits.
              This may precipitate the next message.

       write failed, Broken pipe
              Printed by scanner when a process  rebuilding  a  save  stream's
              indexes exits before consuming the entire stream.

       You are not authorized to run this command
              A normal (non-root) user invoked this command.

       could not convert 'arg' to a file number
              The  -f and -r options require a numeric argument for the start-
              ing file or record number of the media.

       already exists in the media index
              The -i or -m option was specified and  the  volume  was  already
              listed  in  the media database.  This message is purely informa-
              tional, and means that the volume is  not  being  added  to  the
              media database because it is already listed there.

       fn %d rn 0 read error I/O error
       done with tape_type tape volid volume_name
              These  messages,  when  occurring together, are a consequence of
              scanner encountering consecutive filemarks at end of the  media.
              They do not indicate an error condition and can be ignored.

LIMITATIONS

       scanner  can  run  without the NetWorker services (for example, nsrd(1)
       and nsrmmdbd(1)) when not reconstructing the media or the  online  file
       indexes  with most device types. For logical and NDMP devices, the Net-
       Worker services have to be running in order to query these device  con-
       figurations.

       File  index  backups imported from volumes from other NetWorker servers
       cannot be recovered by nsrck -L7.  You must use mmrecov to recover  the
       Bootstrap  of  that  NetWorker  server  before  the file indexes can be
       recovered.

       When scanning a relabeled optical volume (that is, a re-writable  opti-
       cal volume that had been written once, then re-labeled and used again),
       scanner may read off the end of the new data, and attempt to  read  the
       old  data  from the previous version of the volume, terminating with an
       'unexpected volume id' error.  This error occurs after all  the  good
       data has been read, and can be ignored.

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