# Configure custom security realms

You can create a custom security realm that draws from an existing store of users such as directory server on the network. To use a custom security realm, you first create an implementation of the `weblogic.security.acl.AbstractListableRealm` interface or the `weblogic.security.acl.AbstractManageableRealm` interface and then use the Administration Console to install your implementation.

To install a custom security realm:

1. If you have not already done so, in the Change Center of the Administration Console, click Lock & Edit (see Use the Change Center).
2. In the left pane, expand Compatibility Security > Realms and click New.

   The Create a New Basic Realm page appears.

3. In the Name field, enter a name for the custom security realm.
4. In the Type drop-down list, select `Custom Realm` and click OK.
5. On the Summary of Security Compatibility: Basic Realms page, click the name of the new Custom realm.

   The Settings page for the Custom security realm appears.

6. On the Settings page for the Custom security realm, set the appropriate attributes for the realm and click Save.
7. Configure the Caching realm. For more information, see Configure Caching realms .

   When configuring the Caching realm, select the LDAP Realm V2 option from the pull-down menu for the Basic Realm attribute on the Caching Realms: Configuration: General page. The Basic Realm attribute defines the association between the Caching realm and the alternate security realm (in this case, the LDAP V2 security realm).

8. In the left pane, select your domain (for example, mydomain).
9. Select Compatibility Security > File Realm.
10. In the Caching Realm field, select the Caching realm to be used with the custom security realm.
11. Reboot WebLogic Server.