Adding a new witness server after a disaster failed with database mirroring error 1456. Here is one possible cause and what to check.
SQL SERVER – AlwaysOn Automatic Seeding – Database Stuck in Restoring State
A client used AlwaysOn automatic seeding for a huge database, but it stayed in Restoring state on the secondary. Here is the reason we found.
SQL SERVER- Unable to Failover AlwaysOn Availability Group to Disaster Recovery Site
A client added a DR node but was unable to failover AlwaysOn Availability Group to it. The listener had only one IP address, and here is the fix.
SQL SERVER – Always On Availability Group Failover Generating Dump. Error: 17066: SQL Server Assertion: HadrFstrVnnUtils.cpp:479
A client’s availability group failover across subnets got stuck in Resolving and generated dumps with Error 17066. Here is what we found and how we fixed it.
SQL SERVER – Always On Availability Group Error 35250: The Connection to the Primary Replica is Not Active
Joining a database to an availability group can fail with Availability Group Error 35250. Here is why it shows up in the wizard and how I fix it.
SQL SERVER – AlwaysOn Availability Group Backup fn_hadr_backup_is_preferred_replica Not Working Correctly
A client’s backups to the secondary never ran because fn_hadr_backup_is_preferred_replica returned 0 on every node. Here is what I found in its code.
SQL SERVER – AlwaysOn Wizard Error – Checking for Compatibility of the Database File Locations on the Server Instance that Hosts Secondary Replica
The AlwaysOn wizard failed while checking database file locations on the secondary replica, though the drives were correct. Here is the workaround.