OpenVMS Cluster Systems - OpenVMS Systems - HP

The OpenVMS Cluster Operating Environment
4.5 Configuring and Starting a Satellite Booting Service
Note
If you plan to use LANCP in place of DECnet, and you also plan to
move from DECnet Phase IV to DECnet–Plus, Compaq recommends the
following order:
1. Replace DECnet with LANCP for satellite booting (MOP downline
load service) using LAN$POPULATE.COM.
2. Migrate from DECnet Phase IV to DECnet-Plus.
There are two cluster configuration command procedures, CLUSTER_CONFIG_
LAN.COM and CLUSTER_CONFIG.COM. CLUSTER_CONFIG_LAN.COM uses
LANCP to provide MOP services to boot satellites; CLUSTER_CONFIG.COM
uses DECnet for the same purpose.
Before choosing LANCP, DECnet, or both, consider the following factors:
• Applications you will be running on your cluster
DECnet task-to-task communications is a method commonly used for
communication between programs that run on different nodes in a cluster or
a network. If you are running a program with that dependency, you need to
run DECnet. If you are not running any programs with that dependency, you
do not need to run DECnet.
• Limiting applications that require DECnet to certain nodes in your cluster
If you are running applications that require DECnet task-to-task
communications, you can run those applications on a subset of the nodes
in your cluster and restrict DECnet usage to those nodes. You can use
LANCP software on the remaining nodes and use a different network, such as
DIGITAL TCP/IP Services for OpenVMS, for other network services.
• Managing two types of software for the same purpose
If you are already using DECnet for booting satellites, you may not want to
introduce another type of software for that purpose. Introducing any new
software requires time to learn and manage it.
• LANCP MOP services can coexist with DECnet MOP services in an OpenVMS
Cluster in the following ways:
Running on different systems
For example, DECnet MOP service is enabled on some of the systems on
the LAN and LAN MOP is enabled on other systems.
Running on different LAN devices on the same system
For example, DECnet MOP service is enabled on a subset of the available
LAN devices on the system and LAN MOP is enabled on the remainder.
Running on the same LAN device on the same system but targeting a
different set of nodes for service
For example, both DECnet MOP and LAN MOP are enabled but LAN
MOP has limited the nodes to which it will respond. This allows DECnet
MOP to respond to the remaining nodes.
Instructions for configuring both LANCP and DECnet are provided in this
section.
4–8 The OpenVMS Cluster Operating Environment