Migrate to a Multiple-Host Cluster

Before migrating your host, check the following:
  • That you have a functional single-host cluster

  • That you have the guide titled Planning and Installing Your Cluster on Linux

  • That, at a minimum, you read and performed the necessary actions listed in "Chapter 2: Plan Your Cluster" in Planning and Installing Your Cluster on Linux. For example,

    • You prepared the additional management hosts and compute hosts to be added to your cluster

    • You set up your file server (HostF) with a shared directory accessible to other hosts in the cluster (/share/ego)

After successfully testing your single-host cluster, you may wish to convert your host into a master host for use in a multiple-host cluster. To do this, you need to reconfigure your host to function in a cluster containing more than one host.

This appendix is intended to be a replacement for "Chapter 3: Install the Master Host" in the Planning and Installing Your Cluster on Linux guide, because you do not need to install a new master host if you migrate your host to a master host.

Note that the database installed with a single-host cluster functions with a multiple-host cluster but is not supported in a production environment. To make the Reporting feature work in a production cluster, you will also have to move to a commercial database, as described in Administering Platform EGO.

The following steps summarize the migration of your single-host cluster to a master host for use in a multiple-host cluster.

  1. Log on to the host as egoadmin.

  2. Set the command-line environment.

  3. Reconfigure the host.

  4. Set the command-line environment.

  5. Start the host.

  6. Test the host role.

Set the command-line environment

On Linux hosts, set the environment before you run any EGO commands. You need to do this once for each session you open. Both root and egoadmin accounts use EGO commands to configure and start the cluster.

You need to reset the environment if the environment changes during your session, for example, if you run egoconfig mghost, which changes the location of some configuration files.

These examples assume the default installation directory /opt/ego.

Reconfigure the host

Reconfigure your single-host cluster for use as a master host in a multiple-host cluster.

Your host currently stores its configuration files in a local directory. You need to redefine your host to store its configuration files in a shared directory so you can add other management hosts to your cluster. This is necessary to convert your single-host cluster into a multiple-host cluster.

Redefine the host as a management host only

Redefine your host to be a management host only. You need a shared directory to store important files.

Take this step on every management host, including all master candidates.

Run the egoconfig mghost command:

egoconfig mghost shared_dir

where shared_dir is the shared directory that will contain important files such as configuration files to support master host failover.

For example
egoconfig mghost /share/ego

After you run egoconfig mghost, the host:

  • Has access to important system files on the shared directory

  • Belongs to the ManagementHosts host group.

Remember:

The shared directory is the same for all management hosts.

Set the environment to make the new configuration take effect.

Set the command-line environment

Set the command-line environment for the shared directory, same as you did for the default directory.

  • For csh or tcsh, use cshrc.ego:

    source /share/ego/kernel/conf/cshrc.ego

  • For sh, ksh, or bash, use profile.ego:

    . /share/ego/kernel/conf/profile.ego

Enable automatic startup

This is optional.

Automatic startup

By default, you must start EGO manually if a host restarts.
Tip:

For ease of administration, you should use egosetrc.sh to enable automatic startup. This feature starts EGO automatically when the host restarts.

Enabling automatic system startup creates an ego link under: /etc/rc.d/init.d

Set automatic startup on your host

Run the command egosetrc.sh.

Start the host

Run egosh to start EGO on your host.
egosh ego start

Test the host role

Make sure the host has been removed from the ComputeHosts group in your cluster:
egosh resource group ComputeHosts

If you cannot see the host name in the Resource List in the ComputeHosts group, the host is successfully configured as a management host only.