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lkID(8)

NAME

lkID - LifeKeeper device identification

SYNOPSIS

lkID -d <device> [-v] [-i [ID] -f]

DESCRIPTION

lkID is used to set or show the LifeKeeper ID for a disk device.

-d <device>

The disk device refers to the entire disk, e.g.  /dev/sda.  If no other parameters are specified the LifeKeeper ID will be printed from this device, if one exists.

-i [ID]

Write an ID to the specified disk. If an ID is provided it should be an ID that will be unique throughout the cluster.  Consider future expansion and reconfigurations when deciding on a unique ID.  If an ID is not provided then the number of clock TICKS from system "EPOCH" (January 1, 1970) will be used to create a unique ID, e.g. "lkID5919599".

-f

If there is data where the ID will be written, whether it is an "old" ID or other data, then this option is needed to overwrite the data.  Before overwriting the data with the ID ensure the space is not being used by another application.  See note below concerning the boot loader.

-v

Print additional information that may be useful when resolving a failure.

 

The ID is used by LifeKeeper to uniquely identify a device and to determine that it is shared storage.  The LifeKeeper ID is useful when other means are not available to identify the device, such as SCSI Inquiry data.

By default the ID will be written in block 0 on the disk device in the area where the boot loader resides.  This restricts the ID to non-boot devices.  The location of the ID can be redefined by setting IDLOCATION in /etc/default/LifeKeeper to either the hard coded block number or a relative negative offset from the beginning of partition 1.  To avoid overwriting the partition information, the ID data written to the disk cannot exceed 446 bytes.

RETURN VALUE

On success, the LifeKeeper ID for the device will be printed to stdout with a return value of 0.  On failure, an error message will be printed to stderr with a return value of 1.

RESTRICTIONS

With the ID stored on the physical media, SCSI reservations cannot be used in conjunction with lkID.  To disable the use of reservations by LifeKeeper, edit /etc/default/LifeKeeper to either add or modify the "RESERVATIONS" variable to be "none", e.g.'RESERVATIONS="none"'.  Due to this restriction it is recommended that the LifeKeeper ID only be used where the default mechanism used by LifeKeeper, SCSI Inquiry data, does not provide a unique ID.

The location where the ID is stored on a disk must be consistent throughout the cluster, e.g. all systems in the cluster must have the same definition of IDLOCATION and each disk must have the LifeKeeper ID stored at that location.

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