We have a customer who has Unity 4.2.1 set up at two different sites in one AD environment, they are not digitally networked together and do not share dialing capabilities between the sites. Recently, the customer experienced saturation of their WAN link between the two sites and it was determined that the Unity messaging system in Site1 was attempting to deliver a message from an unidentified caller to the Unaddressed DL which belonged to the other unity server in Site2 over and over again. The only issue I could find in the Site1 event logs was the NDR that unity couldnt send to the unaddressed DL related to its own server because there were no members of the DL (so I added the Eadmin back in for now until I can get real admin names) however other than that, did not find anything else. I realize that these DLs are part of the global directory and need members in order to be able to send messages but should unity be attempting to send to a DL that is not associated with its own configuration? TAC was engaged but the root cause as to why Unity was sending to the unaddressed DL of the other server was not provided, only the confirmation that it did indeed saturate the WAN link. I also noted that both Eadmin accounts had been left with the default extension, which I have changed as well there are multiple instances of Eadmin and the Unity system DLs in Ad under each of those two site OUs. The customer says they did not re-install unity so there should only be 1 instance of each object, so assuming they must have replication issues as well. (Again, TAC didnt think this was related however I suspect there are more issues here).
