Return
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Title
Poor performance when working with SQL AlwaysOn in a distributed environment -
Description
When working with SQL AlwaysOn, the Active Roles Web Interface and Active Roles Console may show very poor performance. The Active Roles Administration Service may take a long time to start. PerfMon logs indicate that Database changes processed/sec is a potential performance bottleneck. -
Cause
The SQL AlwaysOn listener is likely configured with DNS Round Robin instead of a geographically-aware load balancer.
To confirm this, perform an NSLOOKUP against the listener name which is configured in the Active Roles Configuration Center. If multiple IP Addresses are returned, the listener is likely configured with DNS Round Robin.
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Resolution
WORKAROUND 1
Configure the SQL AlwaysOn listener DNS alias to be load balanced by a geographically-aware appliance.
WORKAROUND 2
On the Active Roles host, configured the HOSTS file so that the DNS alias of the SQL AlwaysOn listener resolves to an IP address in the local site.