bionic (8) o2cluster.8.gz

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

NAME

       o2cluster - Change cluster stack stamped on an OCFS2 file system.

SYNOPSIS

       o2cluster [-o|--show-ondisk] [-r|--show-running] [-u|--update[=<clusterstack>]] [-hvVyn] [device]

DESCRIPTION

       o2cluster  is used to change the cluster stack stamped on an OCFS2 file system.  It also used to list the
       active cluster stack and the one stamped on-disk. This utility does not expect the cluster to be  online.
       It  only  updates  the  file  system if it is reasonably assured that it is not in-use on any other node.
       Clean journals implies the file system is not in-use. This utility aborts if it detects  even  one  dirty
       journal.

       Before  using  this utility, the user should use other means to ensure that the volume is not in-use, and
       more importantly, not about to be put in-use. While clean journals implies the file system is not in-use,
       there  is  a  tiny window after the check and before the update during which another node could mount the
       file system using the older cluster stack.

       If a dirty journal is detected, it implies one of two scenarios. Either the file  system  is  mounted  on
       another  node,  or,  the  last  node  to  have it mounted, crashed. There is no way, short of joining the
       cluster, that the utility can use to differentiate between the two. Considering this utility is targetted
       to  be  used  in  scenarios  when  the  user is looking to change the on-disk cluster stack, it becomes a
       chicken-and-egg problem.

       If one were to run into this scenario, the user should manually re-confirm that the file  system  is  not
       in-use on another node and then run fsck.ocfs2(8). It will update the on-disk cluster stack to the active
       cluster stack, and, do a complete file system check.

SPECIFYING CLUSTER STACK

       The cluster stack can be specified in one of two forms. The  first  as  default,  denoting  the  original
       classic o2cb cluster stack with local heartbeat. The second as a triplet with the stack name, the cluster
       name and the cluster flags separated by commas. Like o2cb,mycluster,global.

       The valid stack names are o2cb, pcmk, and cman.

       The cluster name can be upto 16 characters. The o2cb stack further restricts the names  to  contain  only
       alphanumeric characters.

       The valid flags for the o2cb stack are local and global, denoting the two heartbeat modes. The only valid
       flag for the other stacks is none.

OPTIONS

       -o|--show-ondisk
              Shows the cluster stack stamped on-disk.

       -r|--show-running
              Shows the active cluster stack.

       -u|--update[=<clusterstack>]
              Updates the on-disk cluster stack with the one provided. If no  cluster  stack  is  provided,  the
              utility detects the active cluster stack and stamps it on-disk.

       -v, --verbose
              Verbose mode.

       -V, --version
              Show version and exit.

       -y, --yes
              Always answer Yes in interactive command line.

       -n, --no
              Always answer No in interactive command line.

EXAMPLES

       # o2cluster -r
       o2cb,myactivecluster,global

       # o2cluster -o /dev/sda1
       o2cb,mycluster,global

       # o2cluster --update=o2cb,yourcluster,global /dev/sdb1
       Changing the clusterstack from o2cb,mycluster,global to o2cb,yourcluster,global. Continue? y
       Updated successfully.

SEE ALSO

       debugfs.ocfs2(8)   fsck.ocfs2(8)   fsck.ocfs2.checks(8)   mkfs.ocfs2(8)  mount.ocfs2(8)  mounted.ocfs2(8)
       o2image(8) o2info(1) tunefs.ocfs2(8)

AUTHORS

       Oracle Corporation

       Copyright © 2011, 2012 Oracle. All rights reserved.