Configure duplicate suppression for server-based flexible management
When duplicate suppression and server-based flexible management are
used together, inconsistencies between the servers may arise. Most
of the inconsistencies can be resolved by configuring the duplicate
suppression on each server in exactly the same way. However, there
are some configurations possible, when inconsistencies can only be
resolved by disabling duplicate suppression for forwarded messages
or changing the forwarding configuration.
Scenario 1
Server A forwards Message M1 to Server C.
Server B forwards Message M2 to Server C.
Message M1 arrives first at Server C.
Message M2 is recognized as a duplicate to M1 and is being
attached to M1 as a duplicate annotation and the duplicate count is
being increased (or depending on the configuration just as a
duplicate count increase).
Inconsistency 1
The duplicate count of M1 on Server C is incremented.
Server C forwards the duplicate count of M1 to Server A and
Server B.
Server A increments the duplicate count of M1.
Server B discards the operation as it does not have message
M1.
Inconsistency 2
An Administrator on Server B acknowledges Message M2.
This operation is being forwarded to Server C. Server C does
not know about a Message M2, because it was discarded by duplicate
suppression.
The operation is being discarded without any action.
The original message M1 still exists as well as the duplicate
annotation created by M2.
Resolution for both inconsistencies
Introduce bi-directional forwarding between Server A and Server B.
Configure duplicate suppression on each server in the same way.
Scenario 2
Server A forwards Message M1 to Server C and Server B.
Message M2 arrives on Server B. It is NOT discarded as a
duplicate.
Server B forwards Message M2 to Server C and Server A.
Message M2 is recognized on Server C and Server A as a duplicate.
Server C and Server A forward the duplicate count change operation
to Server B, which increments the duplicate count of Message M1.
Message M2 however is still in the message browser.
Inconsistency
Server B has Message M2 twice, once as real message and again as a
duplicate annotation (or depending on the configuration just as a
duplicate count increase).
Resolution
Configure the duplicate suppression on all servers the same way.
Then Message M2 gets discarded already on Server B and all servers
have a consistent view in the message browser.
To disable duplicate suppression for forwarded messages
In the console tree, right-click Operations Manager, and
then click ConfigureServer.... The
Server Configuration dialog appears.
Click Namespaces, and then click Server-based Flexible
Management.
Set the value of Duplicate detection on forwarded msgs to
false. This disables duplicate message for forwarded messages. This
may help to resolve inconsistencies caused by duplicate
suppression, but may increase the number of messages in the message
browser.
(Setting this value to true may help reduce the number of
messages in the message browser, but has a small performance
impact. )