I have a confusing situation and I need some advice. We have two mail servers running as a cluster. And we have layer three switches (3750) as access switches and the 6509's as core. At the 3750's, we are running EIGRP and configured the access VLAN. Now the problem is as soon as we configure the cluster, we loose connection between the cluster and the Microsoft outlook from the users PC's but we can ping the cluster from the same PC's. with the same switch configurations, we can access the mail should we remove the cluster (use one exchange box). However, should we remove the routing, move the VLAN to the core and configure the 3750's like normal layer 2 access switches with , everything works perfect. we have similar problem with users accessing the exchange server from the WAN.
Any advice will be appreciated