- Mailbox: Clustered Mailbox Server (CMS) - either SCC or CCR, failovers automatically. - Hub Transport: If you have more than one Hubs, they load-balance automaticlly. No action required. - Edge: If Edge servers receive inbound internet mail (are targets of MX records) - this can be done either using multiple MX records, or using network load balancing (MX points to A recort that maps to the virtual ipo address), for outbound mail: Send Connectors can have multiple source servers (like Bridgeheads on SMTP and Routing Group connectors in Exchange 2003). - CAS: Network load balancing -- Bharat Suneja MVP - Exchange www.zenprise.com NEW blog location: exchangepedia.com/blog ------------------------------