[Serusers] ser High Availability

Hi I've been thinking on making a HA setup with multiple ser's. Wat would be the best solution? 1) Sharing a usrloc database? Then I think the only way is to use db_mode 1 (every read out of a database), but would cause a lot of overhead because of every request needs a sqlquery. Method 2 doesn't seem to work, because if I delete a record manually from database, the internal DB doesn't get synced to that 2) evey SER automaticly dials also to all ser's in the clusters, and the one's who have a known location, dial them. Don't know if this would give errors when the same user is connected to multiple ser's? thx Arne