--- name: "debugfs.ocfs2" section: "8" platform: "linux" package: "ocfs2-tools" version: "1.8.8-3" release: "Debian 13 (Trixie)" platforms: ["linux"] url: "https://new.carta.tech/debugfs.ocfs2" --- # debugfs.ocfs2(8) OCFS2 file system debugger. ## NAME debugfs.ocfs2 - OCFS2 file system debugger. ## SYNOPSIS **debugfs.ocfs2** \[**-f** *cmdfile*\] \[**-R** *command*\] \[**-s** *backup*\] \[**-nwV?**\] \[*device*\] - **debugfs.ocfs2** **-l** \[*tracebit* ... \[**allow**\|**off**\|**deny**\]\] ... - **debugfs.ocfs2** **-d, --decode** *lockname* - **debugfs.ocfs2** **-e, --encode** *lock\_type block\_num \[generation \| parent\]* ## DESCRIPTION The **debugfs.ocfs2** program is an interactive file system debugger useful in displaying on-disk **OCFS2** filesystem structures on the specified *device*. ## OPTIONS - **-d, --decode** *lockname* Display the information encoded in the *lockname*. - **-e, --encode** *lock\_type block\_num \[generation \| parent\]* Display the lockname obtained by encoding the arguments provided. - **-f, --file** *cmdfile* Executes the debugfs commands in *cmdfile*. - **-i, --image** Specifies device is an o2image file created by *o2image* tool. - **-l** \[*tracebit* ... \[**allow**\|**off**\|**deny**\]\] ... Control **OCFS2** filesystem tracing by enabling and disabling trace bits. Do *debugfs.ocfs2 -l* to get the list of all trace bits. - **-n, --noprompt** Hide prompt. - **-R, --request** *command* Executes a single debugfs command. - **-s, --superblock** *backup-number* *mkfs.ocfs2* makes up to 6 backup copies of the superblock at offsets 1G, 4G, 16G, 64G, 256G and 1T depending on the size of the volume. Use this option to specify the backup, 1 thru 6, to use to open the volume. - **-w, --write** Opens the filesystem in *RW* mode. By default the filesystem is opened in *RO* mode. - **-V, --version** Display version and exit. - **-?, --help** Displays help and exit. ## SPECIFYING FILES Many **debugfs.ocfs2** commands take a *filespec* as an argument to specify an inode (as opposed to a pathname) in the filesystem which is currently opened by **debugfs.ocfs2**. The *filespec* argument may be specified in two forms. The first form is an inode number or lockname surrounded by angle brackets, e.g., \<32\>. The second form is a pathname; if the pathname is prefixed by a forward slash ('/'), then it is interpreted relative to the root of the filesystem which is currently opened by **debugfs.ocfs2**. If not, the path is interpreted relative to the current working directory as maintained by **debugfs.ocfs2**, which can be modified using the command *cd*. If the pathname is prefixed by a double forward slash ('//'), then it is interpreted relative to the root of the system directory of the filesystem opened by **debugfs.ocfs2**. ## LOCKNAMES Locknames are specially formatted strings used by the file system to uniquely identify objects in the filesystem. Most locknames used by *OCFS2* are generated using the inode number and its generation number and can be decoded using the *decode* command or used directly in place of an inode number in commands requiring a *filespec*. Like inode numbers, locknames need to be enclosed in angle brackets, e.g., \. Use the *encode* command to generate all possible locknames for an object. ## COMMANDS This is a list of the commands which debugfs.ocfs2 supports. - *bmap filespec logical\_block* Display the physical block number corresponding to the logical block number *logical\_block* in the inode *filespec*. - *cat filespec* Dump the contents of inode *filespec* to stdout. - *cd filespec* Change the current working directory to *filespec*. - *chroot filespec* Change the root directory to be the directory *filespec*. - *close* Close the currently opened filesystem. - *controld dump* Display information obtained from ocfs2\_controld. - *curdev* Show the currently open device. - *decode \* Display the inode number encoded in the *lockname*. - *dirblocks \* Display the directory blocks associated with the given *filespec*. - *dlm\_locks \[-f \\] \[-l\] \[\\]...* Display the status of all lock resources in the *o2dlm* domain that the file system is a member of. This command expects the debugfs filesystem to be mounted as *mount -t debugfs debugfs /sys/kernel/debug*. Use *lockname(s)* to limit the output to the given lock resources, *-l* to include contents of the lock value block and *-f \* to specify a saved copy of /sys/kernel/debug/o2dlm/\/locking\_state. - *dump \[-p\] filespec outfile* Dump the contents of the inode *filespec* to the output file *outfile*. If the *-p* is given, set the owner, group, timestamps and permissions information on *outfile* to match those of *filespec*. - *dx\_dump filespec* Display the indexed directory information for the given directory. - *dx\_leaf \* Display the contents of the given indexed directory leaf block. - *dx\_root \* Display the contents of the given indexed directory root block. - *dx\_space filespec* Display the directory free space list. - *encode filespec* Display the lockname for the *filespec*. - *extent \* Display the contents of the extent structure at *block#*. - *findpath \[\\|\\]* Display the pathname for the inode specified by *lockname* or *inode#*. This command does not display all the hard-linked paths for the inode. - *frag filespec* Display the inode's number of extents to clusters ratio. - *fs\_locks \[-f \\] \[-l\] \[-B\] \[\\]...* Display the status of all locks known by the file system. This command expects the debugfs filesystem to be mounted as *mount -t debugfs debugfs /sys/kernel/debug*. Use *lockname(s)* to limit the output to the given lock resources, *-B* to limit the output to only the busy locks, *-l* to include contents of the lock value block and *-f \* to specify a saved copy of /sys/kernel/debug/ocfs2/\/locking\_state. - *group \* Display the contents of the group descriptor at *block#*. - *grpextents \* Display free extents in the chain group. - *hb* Display the contents of the heartbeat system file. - *help, ?* Print the list of commands understood by **debugfs.ocfs2**. - *icheck block# ...* Display the inodes that use the one or more blocks specified on the command line. If the inode is a regular file, also display the corresponding logical block offset. - *lcd directory* Change the current working directory of the **debugfs.ocfs2** process to the *directory* on the native filesystem. - *locate \[\\|\\] ...* Display all pathnames for the inode(s) specified by *lockname*s or *inode#*s. - *logdump \[-T\] slot#* Display the contents of the journal for slot *slot#*. Use *-T* to limit the output to just the summary of the inodes in the journal. - *ls \[-l\] filespec* Print the listing of the files in the directory *filespec*. The *-l* flag will list files in the long format. - *net\_stats \[-f \\] \[interval \[count\]\]* Display the net statistics. This command expects the debugfs filesystem to be mounted at */sys/kernel/debug*. The *interval* is in seconds. Use the *-f* parameter to specify a saved copy of /sys/kernel/debug/o2net/stats. - *ncheck \[\\|\\] ...* See *locate*. - *open device* Open the filesystem on *device*. - *quit, q* Quit **debugfs.ocfs2**. - *rdump \[-v\] filespec outdir* Recursively dump directory *filespec* and all its contents (including regular files, symbolic links and other directories) into the *outdir* which should be an existing directory on the native filesystem. - *refcount \[-e\] filespec* Display the refcount block, and optionally its tree, of the specified inode. - *slotmap* Display the contents of the *slotmap* system file. - *stat \[-t\|-T\] filespec* Display the contents of the inode structure for the *filespec*. The *-t* ("traverse") option selects traversal of the inode's metadata. The extent tree, chain list, or other extra metadata will be dumped. This is the default. The *-T* option turns off traversal to reduce the I/O required when basic inode information is needed. - *stat\_sysdir* Display the contents of all objects in the system directory. - *stats \[-h\] \[-s backup-number\]* Display the contents of the superblock. Use *-s* to display a specific backup superblock. Use *-h* to hide the inode. - *xattr \[-v\] \* Display extended attributes associated with the given *filespec*. ## ACKNOWLEDGEMENT This tool has been modelled after **debugfs**, a debugging tool for ext2. ## SEE ALSO **[fsck.ocfs2(8)](/fsck.ocfs2/8.md)** **[fsck.ocfs2.checks(8)](/fsck.ocfs2.checks/8.md)** **[mkfs.ocfs2(8)](/mkfs.ocfs2/8.md)** **[mount.ocfs2(8)](/mount.ocfs2/8.md)** **[mounted.ocfs2(8)](/mounted.ocfs2/8.md)** **[o2cluster(8)](/o2cluster/8.md)** **[o2image(8)](/o2image/8.md)** **[o2info(1)](/o2info/1.md)** **[ocfs2(7)](/ocfs2/7.md)** **[tunefs.ocfs2(8)](/tunefs.ocfs2/8.md)** ## AUTHOR Oracle Corporation ## COPYRIGHT Copyright © 2004, 2012 Oracle. All rights reserved.