User guide

FLEXnet Licensing End User Guide 39
Selecting Server Machines 4
This chapter helps you decide which machines to use as license server machines.
Resources Used by the Server
This section discusses the resources used by the license server. When you select a server
machine, you may need to take into account the system limits on these resources. For small
numbers of licenses (under about 100), most of these system limits are not a problem on any
workstation.
Sockets
When using TCP/IP ports, each FLEXenabled application connected to a license server uses
one or more sockets. The number of sockets any one FLEXenabled application requires is
dependant on FLEXnet Licensing implementation details; consult your vendor for this
information. The number of sockets available to the license server is defined by the per-process
system limit for file descriptors. The total number of sockets used by the license server is
slightly larger than the total number needed by the FLEXenabled applications which are served
by it.
If the number of sockets required by the license server on a single machine becomes excessive,
then it’s probably good to split the license file into more than one file, onto different servers, to
lighten the networking traffic (which requires the vendor to agree to issue new licenses).
FLEXenabled applications then check out licenses from multiple servers using a license-file list
via the
LM_LICENSE_FILE environment variable.
CPU Time
For small numbers of clients, the license servers use very little CPU time. The servers might
have only a few seconds of CPU time after many days.
For a large number of clients (who are each exchanging heartbeat messages with the server), or
for high checkout/checkin activity levels (hundreds per second), the amount of CPU time
consumed by the server may start to become significant, although, even here, CPU usage is
normally not high. In this case, you may need to ensure that the server machine you select has
enough CPU cycles to spare.