| = Data Retention |
| :idprefix: |
| :idseparator: - |
| :docinfo: shared |
| |
| If you enable `journal-retention-directory` in `broker.xml` a copy of every journal file used by the broker will be kept in this folder. |
| |
| [,xml] |
| ---- |
| <configuration...> |
| <core...> |
| ... |
| <journal-retention-directory unit="DAYS" period="365" storage-limit="10G">history</journal-retention-directory> |
| ... |
| </core> |
| </configuration> |
| ---- |
| |
| The broker will keep a copy of each generated journal file, up to the configured retention period at the unit chosen. |
| In the example above, the system would keep all the journal files up to 365 days. |
| |
| It is also possible to limit the number of files kept in the retention directory. |
| You can define `storage-limit` and older files will be removed when this limit is exceeded. |
| |
| Notice `storage-limit` is optional, but you need to be careful to not run out of disk space in the retention folder or the broker might be shutdown because of a critical IO failure. |
| |
| You can use the CLI tools to inspect and recover data from the history, by just passing the journal folder being the retention directory. |
| |
| Example: |
| |
| [,shell] |
| ---- |
| ./artemis data print --journal ../data/history |
| ---- |
| |
| ==== Paging and Large Messages |
| When retention is enabled, paging and large messages are also stored on the retention folder for replaying, so replay will also work for both paged and large messages. |
| |
| ==== Non Persistent Messages |
| Non persistent messages are never stored anywhere in the broker. If you intend to retain data your producers should be using Durable messages. |
| |
| == Recovering data from retention |
| |
| To recover data from the retention folder, you can use the method link:https://activemq.apache.org/components/artemis/documentation/javadocs/javadoc-latest/org/apache/activemq/artemis/api/core/management/ActiveMQServerControl.html#replay(java.lang.String,java.lang.String,java.lang.String,java.lang.String,java.lang.String)[replay] on the management console: |
| |
| image::images/replay-method.png[align="center"] |
| |
| The broker will scan the set of files accordingly to the parameters you passed and it will send these methods to a target queue that you selected. |
| |
| === CLI recover operation |
| |
| The CLI recover operation is intended as a low level operation, where data is read and recovered directly into a set of journal files. |
| Notice uou should never manipulate journal files that are being used by an active broker as that could risk the integrity of your data files and running broker. |
| |
| [,shell] |
| ---- |
| ./artemis data recovery --journal ../data/history --target ../data/recovered --large-messages ../data/large-messages |
| ---- |
| |
