Adding a Fast Data Directory to existing Forest
16 February 2021 02:29 PM
This article will show you how to add a Fast Data Directory (FDD) to an existing forest.
The fast data directory stores transaction journals and stands. When the directory becomes full, larger stands will be merged into the data directory. Once the size of the fast data directory approaches its limit, then stands are created in the data directory.
Although it is not possible to add an FDD path to a currently-existing forest, it is possible to do the following:
1. Destroy an existing forest configuration (while preserving the data)
2. Recreate a forest with the same name and data, with an FDD added
The queries below illustrate steps one and two of the process. Note that you can also do this with Admin UI.
The query below will delete the forest configurations but not data.
1. Schedule a downtime window for this procedure (DO NOT DO THIS ON A LIVE PRODUCTION SYSTEM)
2. Ensure that all ingestion and merging has stopped
3. Just to be on safer side, take a Backup of the forest first before applying this in Production
3. Detach the forest before running these queries
NOTE: make sure to set the $delete-data parameter to false().
declare namespace html = "http://www.w3.org/1999/xhtml";
let $forest-name := "YOUR_FOREST_NAME"
let $new-fast-data := "YOUR_NEW_FAST_DATA_DIR"
let $old-data := admin:forest-get-data-directory($config, admin:forest-get-id($config, $forest-name))
let $old-large-data := admin:forest-get-large-data-directory($config, admin:forest-get-id($config, $forest-name))