kanidm/book/src/database_maintenance.md

# Database Maintenance

## Reindexing

In some (rare) cases you may need to reindex. Please note the server will sometimes reindex on
startup as a result of the project changing its internal schema definitions. This is normal and
expected - you may never need to start a reindex yourself as a result!

You only need to reindex if you add custom schema elements and you see a message in your logs such
as:

```text
Index EQUALITY name not found
Index {type} {attribute} not found
```

This indicates that an index of type equality has been added for `name`, but the indexing process
has not been run. The server will continue to operate and the query execution code will correctly
process the query - however it will not be the optimal method of delivering the results as we need
to disregard this part of the query and act as though it's un-indexed.

Reindexing will resolve this by forcing all indexes to be recreated based on their schema
definitions.

```bash
docker stop <container name>
docker run --rm -i -t -v kanidmd:/data \
    kanidm/server:latest /sbin/kanidmd reindex -c /data/server.toml
docker start <container name>
```

## Vacuum

Vacuuming is the process of reclaiming un-used pages from the database freelists, as well as
performing some data reordering tasks that may make some queries more efficient. It is recommended
that you vacuum after a reindex is performed or when you wish to reclaim space in the database file.

Vacuum is also able to change the pagesize of the database. After changing `db_fs_type` (which
affects pagesize) in server.toml, you must run a vacuum for this to take effect:

```bash
docker stop <container name>
docker run --rm -i -t -v kanidmd:/data \
    kanidm/server:latest /sbin/kanidmd vacuum -c /data/server.toml
docker start <container name>
```

## Verification

The server ships with a number of verification utilities to ensure that data is consistent such as
referential integrity or memberof.

Note that verification really is a last resort - the server does _a lot_ to prevent and self-heal
from errors at run time, so you should rarely if ever require this utility. This utility was
developed to guarantee consistency during development!

You can run a verification with:

```bash
docker stop <container name>
docker run --rm -i -t -v kanidmd:/data \
    kanidm/server:latest /sbin/kanidmd verify -c /data/server.toml
docker start <container name>
```

If you have errors, please contact the project to help support you to resolve these.