Platform LSF Administration Guide Version 6.2

Adding Hosts Dynamically
Administering Platform LSF
104
Adding Hosts Dynamically
By default, all configuration changes made to LSF are static. You must manually change
the configuration and restart the cluster (or at least all master candidates). Dynamic host
configuration allows you to add hosts to the cluster without manually changing the
configuration.
To enable dynamic host configuration, you must define the following parameters:
◆ LSF_MASTER_LIST and LSF_DYNAMIC_HOST_WAIT_TIME in lsf.conf
◆ LSF_HOST_ADDR_RANGE in lsf.cluster.cluster_name
WARNING
When the dynamic host configuration is enabled, any host will be able to
join the cluster. You can limit which hosts can be LSF hosts with the
parameter LSF_HOST_ADDR_RANGE in lsf.cluster.cluster_name.
How dynamic host configuration works
Master LIM
For dynamic host configuration, the master LIM:
◆ Receives request to add hosts
◆ Informs other master candidates to refresh themselves when a host is added
Master candidate LIMs (LSF_MASTER_LIST)
To enable dynamic host configuration, you must define LSF_MASTER_LIST in
lsf.conf. Specify a list of hosts that are candidates to become the master
host for the cluster.
This set of hosts reads the LSF configuration files when a new host is added to the
cluster; other hosts (slave hosts) only receive the host configuration from master LIM.
LSF_MASTER_LIST also identifies the hosts that need to be reconfigured after
configuration change.
Master candidate hosts are informed when a new host is added. When a master
candidate becomes master host, its LIM receives requests from dynamic hosts to add
them to the cluster.
Master candidate hosts should share LSF configuration and binaries.
If a dynamic host is configured as a static host in lsf.cluster.cluster_name, run
badmin hghostdel to remove the host from the host group as a dynamic member.
Slave hosts
Dynamically added LSF hosts that will not be master candidates are slave hosts (or slave
LIMs). Each dynamic slave host has its own LSF binaries and local
lsf.conf and shell
environment scripts (
cshrc.lsf and profile.lsf). You must install LSF on each
slave host.
If LSF_STRICT_CHECKING is defined in lsf.conf to protect your cluster in
untrusted environments, and your cluster has slave hosts that are
dynamically added, LSF_STRICT_CHECKING must be configured in the local
lsf.conf on all slave hosts.