Considerations for Installing Multi-Instances

Before enabling multi-instance installations, review the following requirements and limitations.

General Requirements

  • The computer where you plan to install multiple instances must have at least one Commvault instance already installed.

  • Each instance must be installed in a different installation directory. During the installation, the installation program automatically defines the directory.

    For example, on a Windows computer, if Instance001 is installed on C:\Program Files\CommVault\ContentStore, then Instance002 is automatically installed on C:\Program Files\CommVault\ContentStore2.

  • Each instance must have a unique set of static TCP port numbers. During the installation, the installation program automatically assigns the port numbers.

    • If you want to change the ports used by an existing instance, see Changing Network Ports.

    • If you plan to install multiple MediaAgent instances on a computer, and you want to use a port other than 8400 for the MediaAgent Communications Service (GxCVD), clients from older Commvault versions might not be able to communicate through that port. Therefore, make sure that the port is accessible by the clients that use the MediaAgent.

    • If you already have an instance on a computer and install another instance on the same computer, then the EvMgRC service uses the same port for the second instance. To change the port numbers used by an existing instance, see Changing Network Ports.

  • The VSS Provider software, which includes the VSS Provider and/or VSS Hardware Provider packages, cannot be installed on multiple instances. If the VSS Provider is already installed, and you need to install an agent that requires the VSS Provider software, make sure that the VSS packages are not selected for installation.

  • New instances can point to the same CommServe computer or to a different CommServe computer.

    • To point to a different CommServe computer, you can use the same client name and host name that you specified on the existing instance.

    • To point to the same CommServe computer, you must provide a unique client name.

  • On UNIX, Linux, and Macintosh computers, the installation of additional instances changes the permissions of the entire /etc/CommVaultRegistry directory and its sub-directories. Therefore, non-root users must be members of the same user group that is used for installations. The group permissions must have the default value '7'.

CommServe Software

You can install multiple instances of the CommServe software on cluster group servers. Review the following information for installations on cluster environments:

  • The instance with the CommServe software cannot be used for subsequent installations. If you install additional Commvault software on the cluster server, the software is automatically installed on a new instance.

  • For all cluster group servers that use the same instance, only one set of binaries and one set of services are used, except for the GxClusterPlugin service.


Multiple MediaAgent instances that share libraries with each other must be part of the same CommCell. To be in separate CommCells, the MediaAgents cannot share any libraries.

Exchange Agents

For the Exchange Public Folder Archiver Agent, you must provide a different OWA alias during the installation for each instance that you install.