Hi, Accroding to my understanding, exchange 2003 is using link state to determine the best path to route mail and exchange 2007 is using site link/exchange cost. I'm migrating many many sites's Exchange 2003 to Exchange 2007. In this co-exist enviroment, Two main site (site A & site B) installed two Exchange 2003 and One Exchange 2007 respectively and routing group connector between exchange 03 <-->07 is configured in one main site(A). Recently, the main site(A) Exchage 2007 server down some hours and mail can't be route between Excahnge 03<--> 07 site and between exchange 07<--> 07 site. Any one can suggest me the manuel or auto failover soluton that mails can be route during main site exchange 2007 server down (additional Exchange 2007 Server in site (A)and (B) is not allowed by my .........)? Cyrus

You should create mulliple routing group connectors between 2003 and 2007. You will want to suppress link state updates on your 2003 servers if you create more can on routing group connector. Please read this link for guidance: http://technet.microsoft.com/en-us/library/aa997292(EXCHG.80).aspx Tim Harrington - Catapult Systems - http://HowDoUC.blogspot.com

I'm a little confused. If the server in Site A was down, what are you trying to accomplish?

Hi all, I'm trying to setup a backup mail routing solution when Site A server out of service. I have configured two routing group connector in SITE A and Site B. Mail can be route from Exchange 03 to Exchange 2007 using Site B routing connector when Site A Exchange 2007 Server down, but mail from all Exchange 2007 site to Exchange 2003 site stuck in all Exchange 2007 local. In my understanding Exchange 2007 site link mail routing is always choosing one lowest cost path to route mail. What I'm missing or misunderstanding? Cyrus

By using least cost routing, 2007 will not attempt to re-route a message when a connector is down, it will queue at the point of failure. That is by design. 2003, on the other hand, when Link state updates are enabled, will attempt to re-route the message. However,this was problematic as it could lead to mail loops and make routing troubleshooting difficult. If you have more than one routing group connector, you want to suppress link state updates so 2003 routes messages in the same way as 2007 - which will help prvent mail loops - even though it may seem like a step backwards.

Hi Andy, That means there is no way to setup fault-tolerance routing group connector in Exchange 2007 environment, is it right?

Hi Cyurs, Did you remove the default connector? If no, please remove it and create a new conector between the healthy exchange 2007 server and the exchange 2003 server. Some information for you: http://technet.microsoft.com/en-us/library/aa998645(EXCHG.80).aspx http://technet.microsoft.com/en-us/library/aa997292(EXCHG.80).aspx Regards! Gavin