LSF Version 7.3 - Administering Platform LSF

Administering Platform LSF 155
Platform LSF Licensing
LSF license checkout
Only the master LIM can check out licenses. No other part of LSF has any contact
with the FLEXlm license server daemon. Once LIM on the master host identifies
itself as the master, it reads the
LSF_CONFDIR/lsf.cluster.cluster_name file to
get the host information to calculate the total number of licenses needed. Most LSF
software is licensed per CPU, not per host or per cluster, so multi-processor hosts
require multiple LSF licenses.
After the cluster is properly licensed, the master LIM contacts the license server
daemon periodically to confirm the availability of checked out LSF licenses.
LIM distributes the licenses needed this way:
1 Calculate the total number of licenses needed for the master LIM.
2 Before slave LIMs contact the master, calculate the total number of licenses
needed for all LSF server hosts and check them out. When the slave LIMs start,
they contact the master host to get the licenses they need.
3 Check out licenses needed for client hosts listed in
LSF_CONFDIR/lsf.cluster.cluster_name. If the license checkout fails for
any host, that host is unlicensed. The master LIM tries to check out the license
later.
LSF license grace period
If the master LIM finds the license server daemon has gone down or is unreachable,
LSF has a grace period before the whole cluster is unlicensed. As long as the master
LIM that originally received the licenses is not restarted or shut down, the LSF
cluster can run up to 60 hours without licenses. If you reconfigure LSF after the
license server daemon becomes unavailable, you lose the grace period and the
cluster is unlicensed because the original LIM that carries the correct license
information is killed and restarted during reconfiguration. This prevents LSF from
becoming a single point of failure and enables LSF to function reliably over an
extended period of time (for example, over a long weekend) should the license
server daemon fail.
Unlicensed cluster
While LSF cannot contact a license server daemon, LSF commands are
automatically resubmitted, not aborted.