Redundant Server Licenses

A redundant server license is a special type of license for use in mission-critical environments. It relies on not one license server but three, of which at least two must be active to authorize Xpress. This way, if one license server machine happens to fail, your applications can still use Xpress using the remaining two servers until the problem is corrected.

To obtain a redundant server license, contact your supplier.

1. You must install the license server application on all three license server machines. Edit your server license file and ensure that the machine names in the use_server lines match with the names of your three license server machines. For example:

   use_server server="main_server" hostid="mx001731e8216c"	
   use_server server="backup_server_1" hostid="mx002831e8216d"
   use_server server="backup_server_2" hostid="mx0017ff88216e"

   Install the same server license file on all three redundant server machines.
2. In the client license, list the three redundant license servers, marked as redundant license servers, as follows:

   use_server server="main_server" redundant="1"
   use_server server="backup_server_1" redundant="1"
   use_server server="backup_server_2" redundant="1"

   Xpress will try to connect to each of the redundant license servers in turn, until it successfully establishes a connection with one of them.

Keep in mind that you cannot use Xpress when only one redundant license server is active. Xpress will only license successfully if two or three of the redundant license servers are available.