Am making preliminary investigation into a replication solution between two sites. Each site will have from 50 to 100 users. Services used will be - domain controller, dns, file sharing, Exchange or another mail server (maybe Kerio or mdaemon), possibly Sharepoint, a software licensing server, and that's about it for the moment. The sites will be connected together by fibre (possibly 1GB), and will probably have dual ADSL to the web, or maybe something a bit better. The two sites are 3 miles apart. What we want to achieve is a continuous data protection situation in which if one server goes down, all services and data remain available at the other site. Would would you guys suggest?

1. Domain controller high availbility is easy, install AD DC in other site and configure different in ad sites and services. 2. mail - use exchange 2010 and Database availability feature 3. sharepoints i guess u can have server farm and SQL fault tolerance 4. file server u can use Distributed file sharing (DFS) note: you whole solution goes for toss if wan link also breaks Thanks Uday Kiran, Senior Consultant Cyquent Technology Consultants, Dubai Please Mark as answer if it helps you

Thanks. What about virtualisation, SAN mirroring etc?

you can use virtualization to above Microsoft technologies (hyper-v). SAN Mirroring is also good provided you can afford it. its completely your orgnization decision how much money they would like to invest in high availability. Each technology has their recommended raid types, please check thatThanks Uday Kiran, Senior Consultant Cyquent Technology Consultants, Dubai Please Mark as answer if it helps you