About I/O fencing configuration files
Table: I/O fencing configuration files lists the I/O fencing configuration files.
Related information
Table: I/O fencing configuration files
| File | Description |
|---|---|
| /etc/default/vxfen | This file stores the start and stop environment variables for I/O fencing\: |
| - VXFEN_START - Defines the startup behavior for the I/O fencing module after a system reboot. Valid values include: 1 - Indicates that I/O fencing is enabled to start up. 0 - Indicates that I/O fencing is disabled to start up. | |
| - VXFEN_STOP - Defines the shutdown behavior for the I/O fencing module during a system shutdown. Valid values include: 1 - Indicates that I/O fencing is enabled to shut down. 0 - Indicates that I/O fencing is disabled to shut down. | |
| The installer sets the value of these variables to 1 at the end of VCS configuration. | |
| If you manually configured VCS, you must make sure to set the values of these environment variables to 1. | |
| /etc/vxfendg | This file includes the coordinator disk group information. |
| This file is not applicable for server-based fencing and majority-based fencing. | |
| /etc/vxfenmode | This file contains the following parameters\: |
| - vxfen_mode scsi3 - For disk-based fencing. customized - For server-based fencing. disabled - To run the I/O fencing driver but not do any fencing operations. majority - For fencing without the use of coordination points. | |
| - vxfen_mechanism This parameter is applicable only for server-based fencing. Set the value as cps. | |
| - scsi3_disk_policy dmp - Configure the vxfen module to use DMP devices The disk policy is dmp by default. If you use iSCSI devices, you must set the disk policy as dmp. Note: You must use the same SCSI-3 disk policy on all the nodes. | |
| - List of coordination points This list is required only for server-based fencing configuration. Coordination points in server-based fencing can include coordinator disks, CP servers, or both. If you use coordinator disks, you must create a coordinator disk group containing the individual coordinator disks. Refer to the sample file /etc/vxfen.d/vxfenmode_cps for more information on how to specify the coordination points and multiple IP addresses for each CP server. | |
| - single_cp This parameter is applicable for server-based fencing which uses a single highly available CP server as its coordination point. Also applicable for when you use a coordinator disk group with single disk. | |
| - autoseed_gab_timeout This parameter enables GAB automatic seeding of the cluster even when some cluster nodes are unavailable. This feature is applicable for I/O fencing in SCSI3 and customized mode. 0 - Turns the GAB auto-seed feature on. Any value greater than 0 indicates the number of seconds that GAB must delay before it automatically seeds the cluster. -1 - Turns the GAB auto-seed feature off. This setting is the default. | |
| - detect_false_pesb 0 - Disables stale key detection. 1 - Enables stale key detection to determine whether a preexisting split brain is a true condition or a false alarm. Default: 0 Note: This parameter is considered only whenvxfen_mode=customized. | |
| /etc/vxfentab | When I/O fencing starts, the vxfen startup script creates this /etc/vxfentab file on each node. The startup script uses the contents of the /etc/vxfendg and /etc/vxfenmode files. Any time a system is rebooted, the fencing driver reinitializes the vxfentab file with the current list of all the coordinator points. |
| Note: The /etc/vxfentab file is a generated file; do not modify this file. | |
| For disk-based I/O fencing, the /etc/vxfentab file on each node contains a list of all paths to each coordinator disk along with its unique disk identifier. A space separates the path and the unique disk identifier. An example of the /etc/vxfentab file in a disk-based fencing configuration on one node resembles as follows: | |
| - DMP disk: lang=txt /dev/vx/rdmp/rhdisk75 HITACHI%5F1724-100%20%20FAStT%5FDISKS%5F6 00A0B8000215A5D000006804E795D075 /dev/vx/rdmp/rhdisk76 HITACHI%5F1724-100%20%20FAStT%5FDISKS%5F6 00A0B8000215A5D000006814E795D076 /dev/vx/rdmp/rhdisk77 HITACHI%5F1724-100%20%20FAStT%5FDISKS%5F6 00A0B8000215A5D000006824E795D077 | |
| For server-based fencing, the /etc/vxfentab file also includes the security settings information. | |
| For server-based fencing with single CP server, the /etc/vxfentab file also includes the single_cp settings information. | |
| This file is not applicable for majority-based fencing. |