I'm using MS TMG 2010 Standard as my single firewall to publish my Exchange Server and IIS website to the internet, however it is just one VM in the DMZ network with just one network card (vNIC), what sort of redundancy method that is suitable for making this firewall VM redundant / automatically failover in my DR site ?
Because it is very important in the event of disaster recovery all important email through various mobile device will still need to operate and it is impossible if this TMG 2010 VM is offline.
is it by using: 1. Multicast NLB 2. Any other clustering 3. VMware HA / FT (one VM in production, the other VM in DR site with different subnet ?)
Any suggestion and idea willl be appreciated.