Session persistence of a load balancer allows the same server to serve all requests after a session is established with that server. The session persistence is enabled on the load balancer to direct subsequent requests from each unique session to the same vRealize Automation server in the load balancer pool. The load balancer also handles failover for the vRealize Automation Server (Manager Service) because only one Manager Service is active at any one time. Session persistence is not enabled because it is not a required component for the Manager Service.

Load Balancer Design Decisions

Decision ID

Design Decision

Design Justification

Design Implication

SDDC-CMP-012

Set up a load balancer for all vRealize Automation services that support active/active or active/passive configurations.

Required to enable vRealize Automation to handle a greater load and obtain a higher level of availability than without load balancers.

Additional configuration is required to configure the load balancers.

SDDC-CMP-013

Configure load balancer for vRealize Automation Server Appliance, Remote Console Proxy, and IaaS Web to utilize Round-Robin algorithm with Source-IP based persistence with a 1800 second timeout.

Round-robin provides a good balance of clients between both appliances, while the Source-IP ensure that individual clients remain connected to the same appliance. 1800 second timeout aligns with the vRealize Automation Appliance Server sessions timeout value. Sessions that transfer to a different vRealize Automation Appliance may result in a poor user experience.

None

SDDC-CMP-014

Configure load balancer for vRealize Iaas Server and vRealize Orchestrator to utilize Round-Robin algorithm without persistence.

Round-robin provides a good balance of individual requests from the vRealize Server to the vRealize Orchestrator. This will distribute requests equally between the configured vRealize Orchestrator servers to allow the performance capacity of both to be best utilized.

vRealize Automation IaaS Server is Active/stand-by architecture, there for all request will go to a single node only.

None

Consider the following load balancer characteristics for vRealize Automation.

Load Balancer Application Profile Characteristics

Server Role

Type

Enable SSL Pass-through

Persistence

Expires in (Seconds)

vRealize Automation - Persistence

HTTPS (443)

Enabled

Source IP

1800

vRealize Automation

HTTPS (443)

Enabled

Load Balancer Service Monitoring Characteristics

Monitor

Interval

Timeout

Max Retries

Type

Expected

Method

URL

Receive

vRealize Automation Appliance

3

9

3

HTTPS

204

GET

/vcac/services/api/health

vRealize Automation IaaS Web

3

9

3

HTTPS

GET

/wapi/api/status/web

REGISTERED

vRealize Automation IaaS Manager

3

9

3

HTTPS

GET

/VMPSProvision

ProvisionService

vRealize Orchestrator

3

9

3

HTTPS

GET

/vco/api/healthstatus

RUNNING

Load Balancer Pool Characteristics

Server Role

Algorithm

Monitor

Members

Port

Monitor Port

vRealize Automation Appliance

Round Robin

vRealize Automation Appliance monitor

vRealize Automation Appliance nodes

443

443

vRealize Automation Remote Console Proxy

Round Robin

vRealize Automation Appliance monitor

vRealize Automation Appliance nodes

8444

443

vRealize Automation IaaS Web

Round Robin

vRealize Automation IaaS Web monitor

IaaS web nodes

443

443

vRealize Automation IaaS Manager

Round Robin

vRealize Automation IaaS Manager monitor

IaaS Manager nodes

443

443

vRealize Orchestrator

Round Robin

vRealize Automation Orchestrator monitor

vRealize Orchestrator nodes

8281

8281

Virtual Server Characteristics

Protocol

Port

Default Pool

Application Profile

HTTPS

443

vRealize Automation Appliance Pool

vRealize Automation - Persistence Profile

HTTPS

443

vRealize Automation IaaS Web Pool

vRealize Automation - Persistence Profile

HTTPS

443

vRealize Automation IaaS Manager Pool

vRealize Automation Profile

HTTPS

8281

vRealize Orchestrator Pool

vRealize Automation Profile

HTTPS

8444

vRealize Automation Remote Console Proxy Pool

vRealize Automation - Persistence Profile