Environment variables provide each ArcGIS or ArcSDE client the ability to define one or more license servers. Typically environment variables will be used by ArcInfo Workstation or ArcSDE users. These variables are set in a client's environment, not on the server side.
Environment Variable Search Order
ArcGIS and ArcSDE client installations use environment variables to search for a valid license manager.
Important notes when setting up environment variables:
The ESRI_LICENSE_FILE and LM_LICENSE_FILE environment variable settings take precedence over the license manager you are using for ALL your ArcGIS applications. This variable setting will override the license manager chosen during installation, and the license manager set in the Desktop Administrator. Make certain that the license server(s) you specify in these environment variables contain all the necessary features.
Once an application has connected to a valid license manager, no other license manager can be accessed by that application during that session.
The environment variable uses the first valid server found. A license manager is considered valid if it is currently running and contains the license feature the application is looking for. The license manager is still considered valid even if all the license features are in use. Therefore, an environment variable does not guarantee that a license will always be available.
The applications search for a valid license manager in the following order:
1. ESRI_LICENSE_FILE
2. LM_LICENSE_FILE*
3. The sysgen directory in ARCHOME or SDEHOME.
1. ESRI_LICENSE_FILE
2. LM_LICENSE_FILE*
3. LICENSE_SERVER registry entry found under:
HKEY_LOCAL_MACHINE>SOFTWARE>ESRI>License
Direct Connect:
1. ESRI_ARCSDE_LICENSE_FILE**
2. ESRI_LICENSE_FILE
3. LM_LICENSE_FILE*
*We strongly suggest ESRI software clients use the ESRI_LICENSE_FILE variable rather than LM_LICENSE_FILE. Historically, the LM_LICENSE_FILE variable was used, but as more software vendors incorporated FLEXlm into their software, collision problems using this variable began to occur. At FLEXlm v4.1, GLOBEtrotter Software Inc. (GSI) introduced the vendor specific environment variables such as ESRI_LICENSE_FILE.
**The ESRI_ARCSDE_LICENSE_FILE variable is new at 8.1. For a Read\Write connection, Direct Connect users must set this variable to specify a license server that contains an ArcSDE feature. The license manager in the ESRI_ARCSDE_LICENSE_FILE variable can be different than the license manager specified during installation or specified in the Desktop Administrator. The ArcGIS applications (ArcMap, ArcCatalog, ArcGIS extensions) are not affected by the ESRI_ARCSDE_LICENSE_FILE variable. These applications will continue to use the license manager you specified during your ArcGIS installation and to change your license manager in the ArcGIS Desktop Administrator.
1) Defining the path to one or more license files
2) Defining <port>@<host> to one or more license servers
Defining multiple license servers:
There is a limitation to defining multiple license servers. Once an ArcGIS or ArcSDE session is started, that client session is assigned to the specific license server from which its initial license was checked out. From then on, the only extension licenses available to that particular session are those available on from the currently assigned license server. A client cannot simultaneously connect to multiple license servers.
For example, you defined your ESRI_LICENSE_FILE variable with server A listed first and server B listed second. The applications will first look for server A. If server A is not running or does not contain the license features the application is requesting, the applications will connect to server B.
Example 1: Server A has ArcSDE and GRID licenses while server B has only ArcInfo licenses. When you start ArcInfo, your client session determines there are no ArcInfo licenses available on server A, so your client session checks out an ArcInfo license from server B. When you decide to start GRID, you will receive an error message because your client session is assigned to server B, where no GRID licenses exist.
Example 2: Server A and Server B both have ArcInfo licenses. All the licenses are currently being used on Server A. When you start ArcInfo, your client session determines that Server A is running and contains the ArcInfo feature. The license manager is still considered valid even though all the ArcInfo licenses are in use and will NOT automatically switch to Server B.