o2cb服务说明

O2CB是OCFS2集群运行所需的一组集群服务。
OCFS2 与其自己的集群堆栈 O2CB 捆绑在一起。
该堆栈包括：

所有的集群服务都已经打包在 o2cb 系统服务中。
OCFS2 操作，如格式化、挂载等，要求 O2CB 集群服务至少在将要执行操作的节点上启动。
ocfs2-tools RPM 包提供了 o2cb 配置文件。

配置o2cb

要在启动时启动 o2cb 服务，请运行“/etc/init.d/o2cb configure”命令：

# /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) [n]:

“o2cb configure”会将更改保存到文件 /etc/sysconfig/o2cb 中。
此类文件的示例：

# cat /etc/sysconfig/o2cb
# This is a configuration file for automatic startup of the O2CB
# driver.  It is generated by running /etc/init.d/o2cb configure.
# Please use that method to modify this file
#
# O2CB_ENABELED: 'true' means to load the driver on boot.
O2CB_ENABLED=true
# O2CB_BOOTCLUSTER: If not empty, the name of a cluster to start.
O2CB_BOOTCLUSTER=ocfs2
# O2CB_HEARTBEAT_THRESHOLD: Iterations before a node is considered dead.
O2CB_HEARTBEAT_THRESHOLD=
# O2CB_IDLE_TIMEOUT_MS: Time in ms before a network connection is considered dead.
O2CB_IDLE_TIMEOUT_MS=
# O2CB_KEEPALIVE_DELAY_MS: Max time in ms before a keepalive packet is sent
O2CB_KEEPALIVE_DELAY_MS=
# O2CB_RECONNECT_DELAY_MS: Min time in ms between connection attempts
O2CB_RECONNECT_DELAY_MS=

服务控制

按需管理o2cb服务，使用服务工具或者直接运行/etc/init.d/o2cb脚本：

# /sbin/service o2cb help
Usage: /etc/init.d/o2cb {start|stop|restart|force-reload|enable|disable|configure|load|unload|online|offline|force-offline|status}
# /etc/init.d/o2cb help
Usage: /etc/init.d/o2cb {start|stop|restart|force-reload|enable|disable|configure|load|unload|online|offline|force-offline|status}

可用的命令有：