bionic (8) mount.ocfs2.8.gz

Provided by: ocfs2-tools_1.8.5-3ubuntu1_amd64 bug

NAME

       mount.ocfs2 -  mount an OCFS2 filesystem

SYNOPSIS

       mount.ocfs2 [-vn] [-o options] device dir

DESCRIPTION

       mount.ocfs2 mounts an OCFS2 filesystem at dir. It is usually invoked indirectly by the mount(8) command.

OPTIONS

       _netdev
              Indicates  that  the file system resides on a device that requires network access (used to prevent
              the system from attempting to mount these filesystems until the network has been  enabled  on  the
              system).  mount.ocfs2(8)  transparently  appends this option during mount. However, users mounting
              the volume via /etc/fstab must explicitly specify this mount  option  to  delay  the  system  from
              mounting the volume until after the network has been enabled.

       noatime
              The file system will not update access time.

       relatime
              The file system will update atime only if the on-disk atime is older than mtime or ctime.

       strictatime,atime_quantum=nrsec
              The file system will always perform atime updates, but the minimum update interval is specified by
              atime_quantum which defaults to 60 secs. Set it to zero to always update atime. These two  options
              need work together.

       [no]acl
              Enables / disables POSIX ACLs (access control lists) support.

       [no]user_xattr
              Enables / disables extended user attributes.

       commit=nrsec
              Sync  all  data  and  metadata  every  nrsec  seconds. The default value is 5 seconds.  Zero means
              default.

       data=[ordered|writeback]
              Specifies the handling of file data during metadata journalling.

              ordered
                     This is the default mode. Data is flushed to disk before  the  corresponding  meta-data  is
                     committed to the journal.

              writeback
                     Data  ordering is not preserved - data may be flushed to disk after the corresponding meta-
                     data is committed to the journal. This is rumored to be the higher-throughput option. While
                     it  guarantees  internal  file  system  integrity, it can allow old data to appear in files
                     after a crash and journal recovery.

       errors=[remount-ro|errors=panic|errors=continue]
              Specifies the behavior when an on-disk corruption is encountered.

              remount-ro
                     This is the default mode. The file system is remounted read-only.

              panic  The system is halted via panic.

              continue
                     Ignore errors. Just log error message,  return  error  code  to  the  calling  process  and
                     continue.

       localflocks
              This disables cluster-aware flock(2).

       coherency=[full|coherency]
              Specifies  the extent of coherency for the cached file data across the cluster.  This mount option
              works with Linux kernel 2.6.37 and later.

              full   This is the default mode. The file system ensures the cached file data is  coherent  across
                     the cluster for all IO modes.

              buffered
                     The file system only ensures the cached file data coherency for buffered mode IOs.  It does
                     not perform IO serialization  for  direct  IOs.  This  allows  multiple  nodes  to  perform
                     concurrent  direct  IOs  to the same file. This is the recommended mode for volumes hosting
                     database files.

       resv_level=level
              Specifies the level of allocation reservation for files. The higher the value, the more aggressive
              it  is.  Valid  values  are  between  0 (reservation off) to 8 (maximum space for reservation). It
              defaults to 2. This mount option works with Linux kernel 2.6.35 and later.

       dir_resv_level=level
              By default, directory reservation scales with file reserveration.  Users  should  rarely  need  to
              change  this  value.  If  the  file allocation reservation is turned off, this option will have no
              effect. This mount option works with Linux kernel 2.6.35 and later.

       inode64
              Indicates that the file system can create inodes at any location in the  volume,  including  those
              which will result in inode numbers greater than 4 billion.

       [no]intr
              Specifies whether a signal can interrupt IOs. It is disabled by default.

       ro     Mount the file system read-only.

       rw     Mount the file system read-write.

NOTES

       To mount and umount a OCFS2 volume, do:

       # mount /dev/sda1 /mount/path
        ...
       # umount /mount/path

       Users mounting a clustered volume should be aware of the following:

           1. The cluster stack must to be online for a clustered mount to succeed.

           2.  The  clustered  mount  operation  is not instantaneous; it must wait for the node to join the DLM
           domain.

           3. Likewise, clustered umount is also not instantaneous; it involves  migrating  all  mastered  lock-
           resources to the other nodes in the cluster.

       If  the  mount  fails,  detailed  errors can be found via dmesg(8). These might include incorrect cluster
       configuration (say, a missing node or incorrect IP address) or a firewall interfering with  o2cb  network
       traffic. Check the configuration as listed in o2cb(7) or the man page of the active cluster stack.

       To  auto-mount  volumes on startup, the file system tools include an ocfs2 init service.  This runs after
       the o2cb init service has started the cluster. The ocfs2 init service mounts all OCFS2 volumes listed  in
       /etc/fstab.

       # chkconfig --add o2cb
       o2cb 0:off 1:off 2:on 3:on 4:off 5:on 6:off

       $ chkconfig --add ocfs2
       o2cb 0:off 1:off 2:on 3:on 4:off 5:on 6:off

       $ cat /etc/fstab
        ...
       /dev/sda1     /u01     ocfs2     _netdev,defaults     0  0
        ...

SEE ALSO

       debugfs.ocfs2(8)  fsck.ocfs2(8)  mkfs.ocfs2(8) mounted.ocfs2(8) o2cb(7) o2cluster(8) o2image(8) o2info(1)
       tunefs.ocfs2(8)

AUTHORS

       Oracle Corporation

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