Bug 45860

Summary:	Schema update breaks HA LDAP setup
Product:	UCS	Reporter:	Daniel Tröder <troeder>
Component:	LDAP	Assignee:	UCS maintainers <ucs-maintainers>
Status:	RESOLVED WONTFIX	QA Contact:	UCS maintainers <ucs-maintainers>
Severity:	normal
Priority:	P5	CC:	dirk.doerflinger, michelsmidt, requate, schwardt
Version:	UCS 4.2
Target Milestone:	---
Hardware:	Other
OS:	Linux
See Also:	https://forge.univention.org/bugzilla/show_bug.cgi?id=41837
What kind of report is it?:	Feature Request	What type of bug is this?:	---
Who will be affected by this bug?:	---	How will those affected feel about the bug?:	---
User Pain:		Enterprise Customer affected?:
School Customer affected?:	Yes	ISV affected?:
Waiting Support:		Flags outvoted (downgraded) after PO Review:
Ticket number:		Bug group (optional):	External feedback, Further conceptual development, Large environments, Workaround is available
Max CVSS v3 score:

Description Daniel Tröder

2017-12-12 15:03:50 CET

LDAP schema update are distributed to all members of a domain via replication. After adding/modifying the schema the LDAP server is restarted.

In a domain where multiple LDAP servers are creating a HA setup this breaks the availability when multiple hosts restart their LDAP serve at the same time.

Implement some kind of domain wide locking mechanism to prevent simultaneous LDAP server restarts.

Workaround: 
The currently used workaround of a customer is to manually stop the listener service on half the servers, run the update, wait till the other servers LDAP have restarted, then manually start the listener on the servers where it was stopped.

Comment 1 Arvid Requate

2017-12-12 15:32:11 CET

Bug 41837 proposes an approach to avoid the slapd restart.

Comment 2 Ingo Steuwer

2020-07-03 20:51:09 CEST

This issue has been filed against UCS 4.2.

UCS 4.2 is out of maintenance and many UCS components have changed in later releases. Thus, this issue is now being closed.

If this issue still occurs in newer UCS versions, please use "Clone this bug" or reopen it and update the UCS version. In this case please provide detailed information on how this issue is affecting you.