NetWorker: LDAP Integration Failing with "LDAP: error code 12 - Unavailable Critical Extension"

Summary: NetWorker Lightweight Directory Access Protocol (LDAP) integration is failing with [LDAP: error code 12 - Unavailable Critical Extension]. This KB is applicable to LDAP server integration and does not apply when backend authentication is Microsoft Active Directory (AD) ...

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Symptoms

  • The external authentication provider is an LDAP server. This issue is not applicable to Microsoft Active Directory (AD) servers.
  • The external authority integration wizard or the authc-create-ldap-config script the following error appears
Error executing command. Failure: 400 Bad Request. Server message: Failed to verify configuration LDAP_SERVER_NAME: [LDAP: error code 12 - Unavailable Critical Extension];
nested exception is javax.naming.OperationNotSupportedException: [LDAP: error code 12 - Unavailable Critical Extension]; remaining name 'ou=People,dc=DOMAIN,dc=DOMAIN'

Cause

This can happen if there is a "query limit" on the LDAP server is being exceeded.

The LDAP logs on the LDAP server contains something like: 
[DD/MM/YYYY:HH:MM:SS -0500] conn=99012497 op=-1 msgId=-1 - fd=1408 slot=1408 LDAP connection from IP_ADDR to IP_ADDR
[DD/MM/YYYY:HH:MM:SS -0500] conn=99012497 op=0 msgId=1 - BIND dn="uid=BIND_ACCOUNT,ou=People,dc=DOMAIN,dc=DOMAIN" method=128 version=3
[DD/MM/YYYY:HH:MM:SS -0500] conn=99012497 op=0 msgId=1 - RESULT err=0 tag=97 nentries=0 etime=0 dn="uid=BIND_ACCOUNT,ou=People,dc=DOMAIN,dc=DOMAIN"
[DD/MM/YYYY:HH:MM:SS -0500] conn=99012497 op=1 msgId=2 - SRCH base="ou=People,dc=DOMAIN,dc=DOMAIN" scope=2 filter="(objectClass=inetOrgPerson)" attrs=ALL
[DD/MM/YYYY:HH:MM:SS -0500] conn=99012497 op=1 msgId=2 - RESULT err=4 tag=101 nentries=1000 etime=1 notes=U
[DD/MM/YYYY:HH:MM:SS -0500] conn=99012497 op=2 msgId=3 - SRCH base="ou=People,dc=DOMAIN,dc=DOMAIN" scope=2 filter="(objectClass=inetOrgPerson)", unsupported critical extension
[DD/MM/YYYY:HH:MM:SS -0500] conn=99012497 op=2 msgId=3 - RESULT err=12 tag=101 nentries=0 etime=0
NOTE: The LDAP administrator must review the logs on the LDAP server.

In this example, the query limit is 1000 which was exceeded.

Resolution

Changed the user search filter to config-user-search-filter="uid={0}"

NOTE: This setting can only be applied when using the authc_config scripts. The external repository in the NetWorker Management Console (NMC) and NetWorker Web User Interface (NWUI) do not have the "Search Filter" field.

The following articles can be used for more information about how to use the authc_config scripts and updating an existing configuration.

Affected Products

NetWorker

Products

NetWorker Family
Article Properties
Article Number: 000034700
Article Type: Solution
Last Modified: 22 Jun 2025
Version:  4
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