H2
Note
GeoServer does not come built-in with support for H2; it must be installed through an extension. Proceed to Installing the H2 extension for installation details.
Installing the H2 extension
- Visit the website download page, locate your release, and download: http://sourceforge.net/projects/geoserver/files/GeoServer/2025.1/extensions/geoserver-2025.1-h2-plugin.zip - Warning - Ensure to match plugin (example 2025.1 above) version to the version of the GeoServer instance. 
- Extract the contents of the archive into the - WEB-INF/libdirectory of the GeoServer installation.
Adding an H2 data store
Once the extension is properly installed H2 will be an option in the Vector Data Sources list when creating a new data store.
 
H2 in the list of vector data stores
Configuring an H2 data store
 
Configuring an H2 data store
Configuring an H2 data store with JNDI
See JNDI.