Invalid Acknowledgement Exception

Hi Everyone,

Actually, I am running webMethods in a Clustered Environment (2 IS’s in the Cluster pointing to same Broker with same Client Prefix). I am running a simple Publish/Subscribe Service, whereby the input from one system to webMethods is Published and then the Subscribers (Only One in my case) receive the document through webMethods.

The Service runs successfully, if the Published document is very small (say 11 text files with 10 data files with 1 record each and last file as meta-data file, which contains the # of records info in each file). However, if the records in data files increases to say 100 records per file and hence the Published document size increases the same Clustered environment behaves strangly and the Subscriber (Only one Subscriber) runs more than once and that, to me, is due to the following Exception: Invalid Acknowledgement (208-1220):

Cannot acknowledge the requested document because the sequence number is out of order with respect to other unacknowledged documents.
while executing trigger.

Unable to ack Document for TriggerStore:AbcInterface.ABC.AbcSubscriber.Trigger:controllerTrigger.

Hope this makes sense to many here and hope to hear back from someone with the solution pretty soon.

Thanks in advance…

Usman Malik