Compaq AA-Q88CE-TE manual Create Journal disk-1 ... ,disk-n, Disk-1, ... disk-n

CREATE JOURNAL

CREATE JOURNAL

Create RTR's recovery journal.

Format

CREATE JOURNAL [disk-1] ... [,disk-n]

Command Qualifiers	Defaults
/CLUSTER	/NOCLUSTER
/BLOCKS=nr-blocks	/BLOCKS=1000
/MAXIMUM_BLOCKS=nr-blocks	/MAXIMUM_BLOCKS=1000
/NODE=node-list	/NODE=default-node-list
/OUTPUT[=file-spec]	/OUTPUT=stdout
/SUPERSEDE	/NOSUPERSEDE

Description

The CREATE JOURNAL command creates RTR's recovery journal files on the specified disks. The target size of the files is specified using the /BLOCKS qualifier (512 byte blocks). The RTR journaling system will attempt to keep the journal file to this size.

The /MAXIMUM_BLOCKS qualifier specifies the maximum size that the journal file can extend to; the RTR journaling system will not extend the journal file beyond this size.

/BLOCKS and /MAXIMUM_BLOCKS are positional qualifiers, so the journal files need not have the same size on each disk.

The CREATE JOURNAL command checks that a journal does not already exist for the node. An error occurs if a journal does exist, unless the /SUPERSEDE qualifier is specified.

When the /SUPERSEDE qualifier is specified, any previously existing journal files are deleted. For this reason the CREATE JOURNAL/SUPERSEDE command should not be issued on a node being started up after a failure if the transactions interrupted by the failure need to be recovered. The CREATE JOURNAL command is normally entered interactively, not automatically from a startup command procedure.

RTR only uses journal files on nodes that are configured to run servers, that is, on backends and on routers with call-out servers.

Parameters

disk-1, ... disk-n

Specifies a list of disk names where the new journal is to reside.

If no disks are specified then the issuer's current default disk will be used.

Spreading the journal over more than one physical disk can improve performance if I/O to the journal file becomes a bottleneck.

RTR Command Line Interface 6–51