Add or Merge Remote Node Definitions
A remote node definition identifies a particular node and a listen address for that node’s Communications server and associates that node and address combination with a vnode name.
When a user uses a vnode name to connect to a database on a remote instance, the local instance must have a remote node definition that defines that vnode name for the remote instance to complete the connection. The netu utility offers two options for adding remote node definitions: add and merge.
Add and merge differ in how they handle the addition of a node definition whose vnode name matches the vnode name of an existing node definition. If you are using the add option, netu overwrites any existing node definitions that have the matching vnode name. If you are using the merge option, netu does not overwrite the existing definitions, but simply establishes another definition. The merge option is very useful if you want to run more than one Communications Server at a server node.
For example, assume that you want to run three Communications Servers at the node “eugenie.” Each server has its own unique listen address for interprocess communications. If you use the add option to establish the remote node definitions for “eugenie” from “napoleon,” you must provide a unique vnode name for each listen address. For example, you have the following vnode name and listen address combinations:
From napoleon:
Royal addr1
Lady addr2
Second addr3
If you use the merge option, you need only one vnode name. Using merge, set up the three node definitions at “napoleon” using the same vnode name for each and simply changing the listen address.
For example:
From napoleon:
Royal addr1
Royal addr2
Royal addr3
When users connect using the vnode name “Royal” Ingres Net connects them to one of the three Communications Servers. Ingres Net automatically tries each server, in random order, until it finds one of the three that is available. Users do not need to remember three vnode names or make three connection attempts. Using merge allows you to keep it simple for users, regardless of how many Communications Servers are running on an installation.
Note: Ingres Net does not allow two definitions that are exactly the same at the same node.
To add or merge a remote node definition
1. Start netu by entering netu at the operating system prompt.
The netu menu appears.
2. Select N (Modify Node Entry) from the menu.
The following prompt appears:
Enter command (add, merge, del, show, exit):
3. Select add or merge. (Type a or m instead of the full word.)
The add and merge options behave differently if the definition you are adding matches an existing vnode name. Be sure to read the paragraphs preceding this procedure before making a choice.
4. Define the account as a private or global account. The default is private.
• To accept the default, press Enter.
• To define a global node entry, enter G. You must be a user with Ingres privileges to define a global node entry.
5. Enter a remote vnode name.
6. Enter the network software type.
7. Enter the remote node address.
8. Enter the listen address of the remote node’s Communications Server.
Netu adds one remote node definition for your local node and displays this prompt:
Enter operation (add, merge, del, show, exit):
9. Select another operation or select exit to Enter to the netu menu.