From the KB article "Configuring Platform Service Controller HA in vSphere 6.5 (2147018)", it seems to me that an external load balancer is still required for seamless PSC HA in v6.5. However, the vSphere 6.5 Upgrade Guide has a section that seems to claim that an external load balancer is no longer required. It talks about raising the "domain functional level" to "2". I can't seem to mind much other documentation that discusses this, so I am wondering if this is a documentation error, or could someone explain it to me in more depth? Here is the blurb from the vSphere 6.5 Upgrade Guide (note the section I highlighted in BOLD):
Upgrade an Environment in Which Platform Services Controller High Availability Is Enabled
In vSphere 5.5 and vSphere 6.0, Platform Services Controller high availability is supported only if a load balancer handles redirection of vCenter Server tra c in case of Platform Services Controller failure. When you upgrade Platform Services Controller and vCenter Server, the resulting environment supports high availability. The load balancer is no longer needed because the Platform Services Controller is capable of handling heavy loads.
Before the upgrade, each node has a domain functional level 1. Failover is handled by an external load balancer.
Prerequisites
Your environment is set up with an external load balancer and Platform Services Controller instances highly available.
Procedure
Upgrade each Platform Services Controller node.
The domain functional level does not change, and the external load balancer continues handling failover.
Enable Platform Services Controller high availability after the upgrade of all Platform Services Controller nodes.
dir-cli domain-functional-level set --level 2
The domain functional level change propagates to the other Platform Services Controller instances.
cmsso-util script, as discussed in the vSphere Installation and Setup documentation.
The vCenter Server nodes are currently pointing to the external load balancer.
After you test that Platform Services Controller high availability works correctly, you can remove the load balancer from your environment.
FYI in case anyone else was wondering this - I heard back from a VMware engineer who confirmed that this is a documentation mistake and will be fixed. An external load balancer is required in both vSphere 6.0 and 6.5 for automated high availability of the PSC nodes.
FYI in case anyone else was wondering this - I heard back from a VMware engineer who confirmed that this is a documentation mistake and will be fixed. An external load balancer is required in both vSphere 6.0 and 6.5 for automated high availability of the PSC nodes.