OCFS2 Integration with HP Serviceguard for Linux Administrator's Guide, Second Edition, May 2009
Table 2-1 HP Serviceguard A.11.18 and OCFS2 Values
OCFS2 Network Idle Timeout (in
seconds/milliseconds)
Cluster Reconfiguration Time (in
seconds/milliseconds) for a
configuration with 8 nodes or less than
8 nodesHeartbeat Intervals (in seconds)
48/4800028/280001
76/7600056/560002
160/160000140/1400005
216/216000196/1960007
300/300000280/28000010
OCFS2 Network Idle Timeout (in
seconds/milliseconds)
Cluster Reconfiguration Time (in
seconds/milliseconds) for a
configuration with more than 8
nodes and less than 16 nodesHeartbeat Intervals (in seconds)
60/6000040/400001
100/10000080/800002
220/220000200/2000005
300/300000280/2800007
420/420000400/40000010
Table 2-2 lists the values that you can use to configure the O2CB_NET_IDLE_TIMEOUT parameter
with HP Serviceguard A.11.19.
Table 2-2 HP Serviceguard A.11.19 and OCFS2 Values
OCFS2 Network Idle Timeout (in
seconds/milliseconds)
Node TOC Time (in
seconds/milliseconds)Member Timeout (in seconds)
45/4500025/2500014
52/5200032/3200018
55/5500035/3500020
61/6100041/4100023
64/6400044/4400025
Configuring the O2CB_HEARTBEAT_THRESHOLD Parameter
The O2CB_HEARTBEAT_THRESHOLD parameter defines the disk heartbeat timeout. It is defined
as the number of 2–second iterations before a node is considered dead.
The default value of this parameter is an integer, which can be converted into a value in seconds.
Following is the formula to convert the timeout in seconds to the number of iterations:
O2CB_HEARTBEAT_THRESHOLD = (((timeout in seconds) / 2) + 1)
In the event of a failure to access devices which have the OCFS2 file system configured from a
node, Serviceguard must be configured to realize this failure first and take the failed node out
of the cluster. OCFS2 must be configured to realize the failure and start recovery actions only
after Serviceguard has taken the failed node out of the cluster, and a stable cluster is formed with
the remaining nodes. This is done to prevent OCFS2 from fencing nodes before Serviceguard
does so. Figure 2-3 describes the sequence of events that occur when a connection to a storage
device is lost from a node.
20 Integrating OCFS2 with HP Serviceguard for Linux