I have 6 instances of sql server that I need to be highly available by being hosted on two sites (one as principal, one as DR). Transparent automatic failover is required. Most are fairly boring and don't do a lot, two are heavily used for writes.
The busiest databases process on average 400,000 tran/min, peaking at 900,000 and generate ~10 gig a day of new data each.
Both sites are the same, both have netapps 15k SAS iscsi sans.
Currently we have win server 2003, sql server standard 2005. Sync mirroring is too slow, and adds 2ms to each transaction.
I've managed to persuade the customer to pay for windows server 2008 and sql server enterprise 2008 with the view of possibly having a failover cluster (with one node in each cluster) between the two sites with netapps doing the cross site replication.
How would you accomplish dual site HA with a single server each site?