Port information

This is a complicated question (unfortunately). By having very robust networking options, it can create confusion, but allows Commvault to work with any type of customer network topology. I mean, we have a full routing solution that allows customers to route networking through multiple clients - amazing! yet all that power is not needed for most environments.

The minimum requirement for most workloads is a single port in a single direction between Commvault components (CommServe/MediaAgent/Client). But this is not how it works out of the box.

Out of the box means that pretty much any port can be used. The CVD process between components will tend to use 8400, but clients will connect to specific services on the CommServe and Media Agents using high ports. These ports are randomly assigned to the CommServe/MA services on startup. You can check them out in the registry at HKEY_LOCAL_MACHINE\SOFTWARE\CommVault Systems\Galaxy\Instance001\Runtime

These are the port numbers for the various services that run. It tries to use the same ports (which are dynamic/ephemeral) but it will pick another one if they are in use at startup. Some of these services are accessed and routed via the CVD process exclusively, others by default will be direct connections from the remote client.

The kicker is, If you configure a networking topology / configuration you can enforce a policy that restricts communications between components (generally speaking) down to a single port in a single direction.

Some examples:

I.e CommServe → Client on Port 8403

Or CommServe ↔ Client on Port 8967

or CommServe ← Client on port 8405

So the answer to your question is very much “it depends” on what you have configured. In release 2024 (11.34) its going to try automatically restrict communications to port 8403 bi-bidirectionally which is a great new feature to reduce configuration for most deployments. All you need to do is ensure 8403 is open on your firewall between Commvault components and it should work.