Before you add an ArcGIS Server machine to a site, you should ensure that it meets the following criteria:
- It must be running on the same operating system platform as the other ArcGIS Server machines in the site. It is recommended that you use the same operating system version and hardware resources for all machines in your site. For example, if you have a site comprised of ArcGIS Server machines, each running on Red Hat Enterprise Linux Server 6 with a 3 GHz processor and 8 GB of RAM, the machine you add to the site should also have the same operating system and hardware specifications.
- It must be at the same version number as the other ArcGIS Server machines in the site.
- It must have the same license applied to it as the other ArcGIS Server machines in the site.
- It must be able to read and write to the site's configuration store and server directories. See About the configuration store and About server directories to learn about this requirement.
- It must be able to communicate with all the other ArcGIS Server machines in the site through the ports listed in Ports used by ArcGIS Server. This may require adjustment of firewall settings.
- It must be able to read any data referenced by services on the site. A good way to verify this is to check whether the machine has permissions to all the data storage locations registered with the site. See About registering your data with ArcGIS Server to learn more about these registered locations.
- All running ArcGIS Server machines need to be able to read and write to the same shared directories through NFS using the same mount point on all systems. For example, if you are mounting a file server shared directory to /arcgis on one machine and using it for your configuration store and server directories, then all machines must also mount that same directory to /arcgis.
- All ArcGIS Server machines need to be running under users who have the same user id (uid) or group id (gid) in order to be able to read and write to the shared configuration store and server directory locations.