VCAP-DCD | Objective 2.2 | Map Service Dependencies

Identify basic service dependencies for infrastructure and application services

Service dependencies come in many forms within a vSphere infrastructure design. Services rely on objects such as DNS, NTP, Active Directory etc. What devices are communicating together? What ports are they communicating on? Which processes make up these services?

VMware did have a product to assist in this, VMware vCenter Application Discovery manager, however this has now gone EOL, and unless you have already purchased it, you wont be able to get your hands on it. The current state analysis that should have already been completed at this point should help here, in particular in identifying the applications that will be migrated. It will then be a manual process to discover and document these dependencies.

I found a good WIKI  from ServiceNow which delves deeper into application dependency mapping. This article explains how relationships are defined using the following:

  • Runs on::Runs
  • Depends on::Used by
  • Hosted on ::Hosts
  • Virtualised by::Virtualises
  • Contains::Contained by
  • IP Connection::IP Connection

They also delve deeper into upstream and downstream relationships, I’d highly recommend giving this page some attention.

Document and reference your findings to ensure every relationship and dependency is covered and accounted for in the design.