Installation guide

Port (Outlet)
Number
po rt Physical plug number or name of virtual machine.
Delay
(optional)
d el ay The number of seconds to wait before fencing is started. The
default value is 0.
lu ci Field cl uster.co n
f At t rib u t e
Descrip t io n
Table A.24, “ SCSI Reservation Fencing” lists the fence device parameters used by fence_scsi , the
fence agent for SCSI persistent reservations.
Note
Use of SCSI persistent reservations as a fence method is supported with the following
limitations:
When using SCSI fencing, all nodes in the cluster must register with the same devices so
that each node can remove another node's registration key from all the devices it is
registered with.
Devices used for the cluster volumes should be a complete LUN, not partitions. SCSI
persistent reservations work on an entire LUN, meaning that access is controlled to each
LUN, not individual partitions.
It is recommended that devices used for the cluster volumes be specified in the format
/d ev/di sk/by-i d /xxx where possible. Devices specified in this format are consistent
among all nodes and will point to the same disk, unlike devices specified in a format such as
/d ev/sda which can point to different disks from machine to machine and across reboots.
T ab le A.24 . SCSI Reservat io n Fen cin g
lu ci Field cl uster.co n
f At t rib u t e
Descrip t io n
Name name A name for the SCSI fence device.
Unfencing unfence
section of the
cluster
configuration
file
When enabled, this ensures that a fenced node is not re-enabled
until the node has been rebooted. This is necessary for non-
power fence methods (that is, SAN/storage fencing). When you
configure a device that requires unfencing, the cluster must first
be stopped and the full configuration including devices and
unfencing must be added before the cluster is started. For more
information about unfencing a node, refer to the fence_no d e(8)
man page. For information about configuring unfencing in the
cluster configuration file, refer to Section 7.3, “ Configuring
Fencing” . For information about configuring unfencing with the
ccs command, refer to Section 5.7.2, “ Configuring a Single
Storage-Based Fence Device for a Node” .
Node name no d ename The node name is used to generate the key value used for the
current operation.
Key for current
action
key (overrides node name) Key to use for the current operation. This
key should be unique to a node. For the "on" action, the key
specifies the key use to register the local node. For the "off"
action,this key specifies the key to be removed from the device(s).
Delay
(optional)
d el ay The number of seconds to wait before fencing is started. The
default value is 0.
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