![]() | Important |
---|---|
The information presented in this section applies to legacy systems where OCFS2 DLM support is not available in Pacemaker. It is preserved here for reference purposes only. New installations should always use the Pacemaker approach. |
OCFS2 uses a central configuration file, /etc/ocfs2/cluster.conf
.
When creating your OCFS2 cluster, be sure to add both your hosts to the cluster configuration. The default port (7777) is usually an acceptable choice for cluster interconnect communications. If you choose any other port number, be sure to choose one that does not clash with an existing port used by DRBD (or any other configured TCP/IP).
If you feel less than comfortable editing the cluster.conf
file
directly, you may also use the ocfs2console
graphical configuration
utility which is usually more convenient. Regardless of the approach
you selected, your /etc/ocfs2/cluster.conf
file contents should look
roughly like this:
node: ip_port = 7777 ip_address = 10.1.1.31 number = 0 name = alice cluster = ocfs2 node: ip_port = 7777 ip_address = 10.1.1.32 number = 1 name = bob cluster = ocfs2 cluster: node_count = 2 name = ocfs2
When you have configured you cluster configuration, use scp
to
distribute the configuration to both nodes in the cluster.
====== SUSE Linux Enterprise systems
On SLES, you may utilize the configure
option of the o2cb
init
script:
/etc/init.d/o2cb configure Configuring the O2CB driver. This will configure the on-boot properties of the O2CB driver. The following questions will determine whether the driver is loaded on boot. The current values will be shown in brackets ('[]'). Hitting <ENTER> without typing an answer will keep that current value. Ctrl-C will abort. Load O2CB driver on boot (y/n) [y]: Cluster to start on boot (Enter "none" to clear) [ocfs2]: Specify heartbeat dead threshold (>=7) [31]: Specify network idle timeout in ms (>=5000) [30000]: Specify network keepalive delay in ms (>=1000) [2000]: Specify network reconnect delay in ms (>=2000) [2000]: Use user-space driven heartbeat? (y/n) [n]: Writing O2CB configuration: OK Loading module "configfs": OK Mounting configfs filesystem at /sys/kernel/config: OK Loading module "ocfs2_nodemanager": OK Loading module "ocfs2_dlm": OK Loading module "ocfs2_dlmfs": OK Mounting ocfs2_dlmfs filesystem at /dlm: OK Starting O2CB cluster ocfs2: OK
====== .Debian GNU/Linux systems
On Debian, the configure
option to /etc/init.d/o2cb
is not
available. Instead, reconfigure the ocfs2-tools
package to enable the
driver:
dpkg-reconfigure -p medium -f readline ocfs2-tools Configuring ocfs2-tools Would you like to start an OCFS2 cluster (O2CB) at boot time? yes Name of the cluster to start at boot time: ocfs2 The O2CB heartbeat threshold sets up the maximum time in seconds that a node awaits for an I/O operation. After it, the node "fences" itself, and you will probably see a crash. It is calculated as the result of: (threshold - 1) x 2. Its default value is 31 (60 seconds). Raise it if you have slow disks and/or crashes with kernel messages like: o2hb_write_timeout: 164 ERROR: heartbeat write timeout to device XXXX after NNNN milliseconds O2CB Heartbeat threshold: `31` Loading filesystem "configfs": OK Mounting configfs filesystem at /sys/kernel/config: OK Loading stack plugin "o2cb": OK Loading filesystem "ocfs2_dlmfs": OK Mounting ocfs2_dlmfs filesystem at /dlm: OK Setting cluster stack "o2cb": OK Starting O2CB cluster ocfs2: OK
When you have completed cluster configuration and created your file system, you may mount it as any other file system:
mount -t ocfs2 /dev/drbd0 /shared
Your kernel log (accessible by issuing the command dmesg
) should
then contain a line similar to this one:
ocfs2: Mounting device (147,0) on (node 0, slot 0) with ordered data mode.
From that point forward, you should be able to simultaneously mount your OCFS2 filesystem on both your nodes, in read/write mode.