“An error was reported while committing a database transaction but it could not be determined whether the transaction succeeded or failed on the database server“-Always on Availability groups

server1(xyz location)-------1GB(N/W)--------server1(abc location)

We have Always on Availability groups Synchronous Configured between server1 and server2 (both got SQL Server 2014 installed)

No issues happened, and we had automatic failover happened without any data loss.

 

server1(xyz location)-------100MB(N/W)--------server2(Colocation)

As soon as we moved to Colocation to a 100MB network between two servers, issues started happening

 “An error was reported while committing a database transaction but it could not be determined whether the transaction succeeded or failed on the database server“

Ref:

https://msdn.microsoft.com/en-us/library/dn135335(v=sql.110).aspx

Synchronous mode :Transaction should be committed on Secondary and send ACK to primary for commit(Automatic Failover)

Asynchronous mode : Transaction  should be committed on Primary and  send ACK to Secondary(Manual Failover)