Getting Started > Client Installation > Installing Windchill RV&S Client > Installing Multiple Windchill RV&S Clients on a Single Machine
  
Installing Multiple Windchill RV&S Clients on a Single Machine
For large organizations using multiple Windchill RV&S servers, it may not be practical to upgrade all servers at the same time. Servers that are maintained by different groups within an organization may operate on independent schedules, upgrading to new releases of the Windchill RV&S server at different times.
To access functionality available in specific releases and connect to different versions of the Windchill RV&S server, individual users may require multiple versions of the Windchill RV&S client installed on a single machine.
Each installation of the Windchill RV&S client contains a corresponding set of configuration and data files. By default, these files are stored in the user's home directory. However, if you need to install multiple versions of the client, then the files for at least one of the versions must be stored in an alternate location.
To specify an alternate location for the client configuration and data files, the MKS_IC_INSTANCE_DIR environment variable must be set in the environment for any Windchill RV&S client that uses the alternate location, and not in the environment for the client version using the home directory.
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The MKS_IC_INSTANCE_DIR environment variable must be set correctly before the corresponding version of the client is launched. If the variable is not set, one version of the client may use the files that correspond to a different version. If a more recent version of the client uses the files for an older client, the files may no longer be usable by the older client.
If you are using a Windows client, you must also explicitly set the port number to avoid a conflict. Linux clients choose a port number at random so they never conflict with one another.
To set the port number, add any non-zero port number to the IntegrityClient.rc file of the Windchill RV&S client, for example:
IntegrityClient.port=1234
A unique port number must be assigned to each client version. It is permissible to allow one client version to continue using the default port number, 31000, by omitting an IntegrityClient.port entry from the corresponding IntegrityClient.rc file.
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Ensure that you are modifying the IntegrityClient.rc file and not the IntegirtyClientSite.rc file. IntegrityClient.rc is a file that is stored in the home directory by default; however, it must be placed in an alternate location for each additional client version you install.