ZCS Administrator Guide 7.2.1
ZCS Administrator Guide 7.2.1
Open Source Edition

Zimbra LDAP Service > Internal Authentication Mechanism

Internal Authentication Mechanism
For accounts stored in the OpenLDAP server, the userPassword attribute stores a salted-SHA1 (SSHA) digest of the user’s password. This information is not used to connect to the directory server; it is only used to compare with the information on the OpenLDAP server, using a pool of re-usable administrator LDAP connections.
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