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OUD12c: Isolated Replica Exhibits a Very Long Start Phase (Doc ID 2662984.1)

Last updated on APRIL 14, 2021

Applies to:

Oracle Unified Directory - Version and later
Information in this document applies to any platform.


On : version,

OUD Isolated Replica Exhibits a Very Long Start Phase

OUD and Patch 27742743 are installed.

The starting of one of the DMZ isolated replicas takes more than 10 Minutes when the isolated replica can not connect by <ADMIN_PORT> the trusted primary server as the traffic is not allowed (admin traffic is allowed only one way from LAN to DMZ) in firewall (FW) .
There are no messages related in any logs.

It would be expected that the startup phase of an isolated replica instance would take a much shorter time.


 The issue can be reproduced at will with the following steps:

1. set environment with an isolated replicated instance in DMZ with FW rules that allow bidirectional traffic between LAN and DMZ for <Replication_Port> , but only unidirectional from LAN to DMZ for the <ADMIN_PORT> traffic
LAN Primary ========= <ADMIN_PORT> =====>>> DMZ isolated replica --- unidirectional
LAN Primary <<<=== <REPLICATION_PORT> ===>>> DMZ isolated replica --- bidirectional

2. start the instance
wait for the start to finish - takes very long - about 10min

An isolated replica is a directory server that can accept changes from other replicas for replay but cannot send changes to the replication server to which it is connected. An isolated replica cannot be the source of data updates to the topology. You can use isolated replicas to separate a directory server from the rest of the replication topology.

Oracle® Fusion Middleware - Administering Oracle Unified Directory 12c (
   32 Replicating Directory Data
      32.15 Understanding Isolated Replicas


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