Clusterless Availability Groups

Allan Hirt talks about clusterless AGs:

A quick history lesson: through SQL Server 2016, we have three main variants of AGs:

  • “Regular” AGs (i.e. the ones deployed using an underlying Windows Server failover cluster [WSFC] requiring Active Directory [AD]; SQL Server 2012+)
  •  AGs that can be deployed without AD, but using a WSFC and certificates (SQL Server 2016+ with Windows Server 2016+)
  • Distributed AGs (SQL Server 2016+)

SQL Server v.Next (download the bits here) adds another variant which is, to a degree, a side effect of how things can be deployed in Linux: AGs with no underlying cluster. In the case of a Windows Server-based install, this means that there could be no WSFC, and for Linux, currently no Pacemaker.

Read on for more details, including limitations and expectations.

Related Posts

Disappearing Availability Groups

Cody Konior has a not-so-great magic trick: I logged onto that node and the AG Dashboard looked okay at first glance. But the test was still failing when I re-ran it manually, so, I looked deeper. I logged onto the second node and noticed the AG was completely gone. All the databases were in recovery […]

Read More

AG Secondary Stats Overwritten With Sample

Taiob Ali has run into an interesting issue: Once I update my statistics with fullscan, with in 10~20 seconds some of the statistics on the same table are getting update on secondary with a sample pecent of rows. Meaning my best statistics are being overwritten with good (full vs sample) statistics. On primary node once […]

Read More

Categories

February 2017
MTWTFSS
« Jan Mar »
 12345
6789101112
13141516171819
20212223242526
2728