PRIMECLUSTER Installation and Administration Guide 4.2 (Linux for Itanium)

5.1.2.3.2 Setting the I/O Completion Wait Time

Set the wait time until I/O completion (WaitForIOComp) during failover triggered by a node failure (panic, etc.) according to the procedure described below.

1. Prechecking the shared disk

   The standard setting for the I/O completion wait time during failover triggered by a node failure (for example, if a panic occurs during MMB asynchronous monitoring) is 0 seconds. However, if a shared disk that requires an I/O completion wait time is being used, this setting must be set to an appropriate value.

   

   All RAID devices manufactured by Fujitsu do not require an I/O completion wait time. Therefore, this setting is not required.

   

   If an I/O completion wait time is set, the failover time when a node failure (panic, etc.) occurs increases by that amount of time.

2. Setting the I/O completion wait time

   Execute the following command, and set the wait time until I/O completion (WaitForIOComp) during failover triggered by a node failure (panic, etc.). For details about the "cldevparam" command, see the "cldevparam" manual page.

   Execute the command in any node that is part of the cluster system.

   # /etc/opt/FJSVcluster/bin/cldevparam -p WaitForIOComp value

   Alternatively, execute the following command and check the setting of the wait time until I/O processing is completed (WaitForIOComp).

   # /etc/opt/FJSVcluster/bin/cldevparam -p WaitForIOComp

   value

3. Starting the shutdown facility

   Check that the shutdown facility has been started on all nodes.

   # /usr/bin/sdtool -s

   If the shutdown facility has already been started, execute the following command to restart the shutdown facility on all nodes:

   # /usr/bin/sdtool -r

   If the shutdown facility has not been started, execute the following command to start the shutdown facility on all nodes.

   # /usr/bin/sdtool -b

4. Checking the status of the shutdown facility

   Check the status of the shutdown facility on all nodes.

   # /usr/bin/sdtool -s