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jfs_tune(8) [centos man page]

jfs_tune(8)						  Set JFS file system parameters.					       jfs_tune(8)

NAME

       jfs_tune - adjust tunable file system parameters on JFS

SYNOPSIS

       jfs_tune [options] device

DESCRIPTION

       jfs_tune adjusts tunable parameters on a Linux JFS file system or external journal.  jfs_tune must be run as root.

       device  is the special file name corresponding to the actual device (e.g. /dev/hdb1) on which a JFS file system or JFS external journal has
       been created.

OPTIONS

       -J device=external-journal
	      Attach the JFS external journal located on external-journal to the JFS file system on device.

	      The external journal must already have been created using the command.  More than one file system may share the same external  jour-
	      nal.

	      mkfs.jfs -J journal_dev external-journal

	      Attach the external journal to the file system by using the command

	      jfs_tune -J device=external-journal device

	      Instead  of  specifying  a  device  name	directly,  external-journal  can also be specified by either LABEL=label or UUID=UUID (Use
	      jfs_tune -l device to display a journal device's volume label and UUID.)

       -l     List the contents of the JFS file system or external journal superblock that resides on device.

       -L volume-label
	      Set the volume label of the JFS file system or external journal.	JFS labels can be at most 16 characters long; if  volume-label	is
	      longer  than  16	characters, jfs_tune will truncate it and print a warning.  The volume label can be used by mount(8), fsck(8), and
	      /etc/fstab(5) (and possibly others) by specifying LABEL=volume_label instead of a block special device name like /dev/hda5.

       -U UUID
	      Set the universally unique identifier (UUID) of the file system or external journal device to UUID.  The format of  the  UUID  is  a
	      series of hex digits separated by hyphens, like this: "c1b9d5a2-f162-11cf-9ece-0020afc76f16".  The UUID parameter may also be one of
	      the following:

		   clear  clear the file system UUID

		   random generate a new randomly-generated UUID

		   time   generate a new time-based UUID

	      The UUID may be used by mount(8), fsck(8), and /etc/fstab(5) (and possibly others) by specifying UUID=uuid instead of a  block  spe-
	      cial device name like /dev/hda1.

	      See uuidgen(8) for more information.

       -V     Print version information and exit (regardless of any other chosen options).

EXAMPLES

       Set a randomly-generated UUID for the JFS file system on the 3rd partition of the 2nd hard disk, and view the resultant superblock:

	      jfs_tune -l -U random /dev/hdb3

       Attach an already existing external journal on a device labeled JFSLog to a JFS file system on /dev/hda8:

	      jfs_tune -J device=LABEL=JFSLog /dev/hda8

REPORTING BUGS

       If you find a bug in JFS or jfs_tune, please report it via the bug tracking system ("Report Bugs" section) of the JFS project web site:
       http://jfs.sourceforge.net/

       Please send as much pertinent information as possible including any error messages resulting from running jfs_tune.

SEE ALSO

       jfs_fsck(8), jfs_mkfs(8), jfs_fscklog(8), jfs_logdump(8), jfs_debugfs(8)

AUTHOR

       Barry Arndt  (barndt@us.ibm.com)

       jfs_tune is maintained by IBM.
       See the JFS project web site for more details:
       http://jfs.sourceforge.net/

								 October 28, 2002						       jfs_tune(8)

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jfs_fscklog(8)						   Extract/Display JFS fsck Log 					    jfs_fscklog(8)

NAME

       jfs_fscklog - extract a JFS fsck service log into a file and/or format and display the extracted file

SYNOPSIS

       jfs_fscklog [ -d ] [ -e device ] [ -f output.file ] [ -p ] [ -V ]

DESCRIPTION

       jfs_fscklog  with option -e device extracts the contents of either the most recent or immediately prior (specified with option -p) JFS fsck
       service log from the specified device, and writes the output to a file.	The file name may be specified with the -f option, or the  default
       file name is <pwd>fscklog.new.  If the -p option is used, the default file name is <pwd>fscklog.old.

       jfs_fscklog with option -d formats and displays the contents of the extracted file.

       jfs_fscklog with options -d and -e device extracts and displays the JFS fsck service log.

OPTIONS

       -d     Format and display a previously extracted JFS fsck service log.

       -e device
	      Extract  the  JFS fsck service log from device and store it in a file.  (device is the special file name corresponding to the actual
	      device from which the fsck log will be extracted (e.g.  /dev/hdb1 )).

       -f file.name
	      Specify the file name, overriding the default file name.	When used with -e device, file.name specifies the name of  the	file  into
	      which the JFS fsck log will be extracted.  When used with -d, file.name specifies the name of the extracted file whose contents will
	      be formatted and displayed.

	      file.name must be 127 characters or less in length.

	      file.name will be created in the present working directory unless it is fully qualified.

       -p     Extract the prior log (as opposed to the most recent log).

       -V     Print version information and exit (regardless of any other chosen options).

EXAMPLES

	Extract the most recent JFS fsck log on /dev/hda5 into <pwd>fscklog.new:

	      jfs_fscklog -e /dev/hda5

       Extract the most recent JFS fsck log on /dev/hdb3 into /temp/l9651107.log:

	      jfs_fscklog -e /dev/hdb3 -f /temp/l9651107.log

       Display the JFS fsck log that was extracted into /temp/l9651107.log:

	      jfs_fscklog -d -f /temp/l9651107.log

       Extract and display the previous JFS fsck log from /dev/hda8:

	      jfs_fscklog -e /dev/hda8 -d -p

REPORTING BUGS

       If you find a bug in JFS or jfs_fscklog, please report it via the bug tracking system ("Report Bugs" section) of the JFS project web site:
       http://jfs.sourceforge.net/

       Please send as much pertinent information as possible, including any jfs_fscklog error messages and the complete output of running jfs_fsck
       with the -v option on the JFS device.

SEE ALSO

       jfs_fsck(8), jfs_mkfs(8), jfs_tune(8), jfs_logdump(8), jfs_debugfs(8)

AUTHOR

       Barry Arndt  (barndt@us.ibm.com)

       jfs_fscklog is maintained by IBM.
       See the JFS project web site for more details:
       http://jfs.sourceforge.net/

								 October 28, 2002						    jfs_fscklog(8)
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