Symas OpenLDAP Knowledge Base

How To Get an OID

Occasionally, an application being developed, a system configuration design, or other requirement you will have to add additional Attributes to an existing Object Class. You may even want or need to define a new Object Class. To do that, you will need to register these new schema elements with the Internet Assigned Numbers Authority (IANA). The IANA operates an online service you can use to get an Object ID (both attributes and object classes are considered “objects” needing a unique ID).

To get a unique Object ID for an Attribute or ObjectClass, please go to

It is never appropriate to make up an OID or use someone else’s. They are free and easy and your OID will be unique. That means that if you ever have to use back-ldap to connect to another directory or back-meta to create a virtual/meta directory, all the OIDs will be unique.