Platform LSF Administration Guide Version 6.2

Chapter 39
Tuning the Cluster
Administering Platform LSF
561
The order in which you specify hosts in LSF_MASTER_LIST is the preferred order for
selecting hosts to become the master LIM.
Considerations
Generally, the files lsf.cluster.cluster_name and lsf.shared for hosts that are
master candidates should be identical.
When the cluster is started up or reconfigured, LSF rereads configuration files and
compares
lsf.cluster.cluster_name and lsf.shared for hosts that are master
candidates.
In some cases in which identical files are not shared, files may be out of sync. This
section describes situations that may arise should
lsf.cluster.cluster_name and
lsf.shared for hosts that are master candidates not be identical to those of the
elected master host.
LSF_MASTER_LIST
undefined
When LSF_MASTER_LIST is not defined, LSF rejects candidate master hosts from the
cluster if their
lsf.cluster.cluster_name and lsf.shared files are different from
the files of the elected master. Even if only comment lines are different, hosts are
rejected.
A warning is logged in the log file
lim.log.master_host_name and the cluster
continues to run, but without the hosts that were rejected.
If you want the hosts that were rejected to be part of the cluster, ensure
lsf.cluster.cluster_name and lsf.shared are identical for all hosts and restart
all LIMs in the cluster with the command:
% lsadmin limrestart all
LSF_MASTER_LIST
defined
When LSF_MASTER_LIST is defined, LSF only rejects candidate master hosts listed
in LSF_MASTER_LIST from the cluster if:
◆ The number of load indices in lsf.cluster.cluster_name or lsf.shared for
master candidates is different from the number of load indices in the
lsf.cluster.cluster_name or lsf.shared files of the elected master.
A warning is logged in the log file
lim.log.master_host_name and the cluster
continues to run, but without the hosts that were rejected.
lsf.shared lsf.cluster.cluster_name
Master LIM
hostB
lsf.conf
hostC
master LIM
candidate
hostD
lsf.conf lsf.conf
slave-only
LIM
hostF
lsf.conf lsf.conf
lsf.conf
LSF_MASTER_LIST=hostC hostD hostE
master LIM
candidate
hostE
slave-only
LIM
hostG
slave-only
LIM
hostH