Remove dynamic hosts

About this task

To remove a dynamic host from the cluster:


Remove a host by setting a timeout value

About this task

LSF_DYNAMIC_HOST_TIMEOUT specifies the length of time (minimum 10 minutes) a dynamic host is unavailable before the master host removes it from the cluster. Each time LSF removes a dynamic host, mbatchd automatically reconfigures itself.

For very large clusters, defining this parameter could decrease system performance. If you want to use this parameter to remove dynamic hosts from a very large cluster, disable the parameter after LSF has removed the unwanted hosts.


In lsf.conf on the master host, define the parameter LSF_DYNAMIC_HOST_TIMEOUT.

To specify minutes rather than hours, append m or M to the value.

For example:

Remove a host by editing the hostcache file

About this task

Dynamic hosts remain in the cluster unless you intentionally remove them. Only the cluster administrator can modify the hostcache file.


  1. Shut down the cluster.


    This shuts down LSF on all hosts in the cluster and prevents LIMs from trying to write to the hostcache file while you edit it.

  2. In the hostcache file $EGO_WORKDIR/lim/hostcache, delete the line for the dynamic host that you want to remove.
    • If EGO is enabled, the hostcache file is in $EGO_WORKDIR/lim/hostcache.

    • If EGO is not enabled, the hostcache file is in $LSB_SHAREDIR.

  3. Close the hostcache file, and then start up the cluster.