Commit log archive configuration

Commit log archiving and point-in-time recovery.

DataStax Enterprise provides commit log archiving and point-in-time recovery. The commit log is archived at node startup and when a commit log is written to disk, or at a specified point-in-time. You configure this feature in the commitlog_archiving.properties configuration file.

The commands archive_command and restore_command expect only a single command with arguments. The parameters must be entered verbatim. STDOUT and STDIN or multiple commands cannot be executed. To workaround, you can script multiple commands and add a pointer to this file. To disable a command, leave it blank.

commitlog archiving properties

The location of the commitlog_archiving.properties file depends on the type of installation:

Package installations	/etc/dse/cassandra/commitlog_archiving.properties
Tarball installations	`installation_location`/resources/cassandra/conf/commitlog_archiving.properties

Procedure

Archive a commit log segment:


Command	archive_command=
Parameters	%path	Fully qualified path of the segment to archive.
Parameters	%name	Name of the commit log.
Example	archive_command=/bin/ln %path /backup/%name

Restore an archived commit log:


Command	restore_command=
Parameters	%from	Fully qualified path of the archived commitlog segment from the `restore_directories`.
Parameters	%to	Name of live commit log directory.
Example	restore_command=cp -f %from %to

Set the restore directory location:


Command	restore_directories=
Format	`restore_directories=restore_directory_location`

Restore mutations created up to and including the specified timestamp:


Command	restore_point_in_time=
Format	<timestamp> (YYYY:MM:DD HH:MM:SS)
Example	restore_point_in_time=2013:12:11 17:00:00

Restore stops when the first client-supplied timestamp is greater than the restore point timestamp. Because the order in which the database receives mutations does not strictly follow the timestamp order, this can leave some mutations unrecovered.