# Cluster Elements

## Purpose

In a standard network, each element is assigned a unique Primary Node Identifier (PNI), which is used to route calls between the elements. In a cluster, however, each element shares the same PNI. Calls are routed between elements using the Cluster Element Identifier (CEID) instead of the PNI. The CEID (also know as the PBX Number) is entered in the Network Elements form and displayed in this form as read-only data.

The Cluster Elements form of each element lists its own CEID (marked "Yes" in the Local column) and the CEIDs of all other cluster elements (marked "No" in the Local column).

For the remote cluster elements, the CEID associates a CEID digit string in the Cluster Elements form with remote directory numbers in the Remote Directory Numbers form. When a user on an element dials the remote directory number of an extension on another element in the cluster, the originating element automatically inserts the CEID digit string of the destination element in front of the dialed directory number. ARS then routes the call to the remote extension based on the CEID digits. The user does not dial the CEID digits to call a remote directory number.

The CEID digit strings of the remote elements must translate into an ARS route, list, or plan, to the corresponding remote element. For example, for the CEID digit string, 7167, any one of the following ARS entries in the ARS Digits Dialed form will satisfy the requirement for a corresponding ARS entry.

NOTE: For the cluster element designated as "Local", the CEID digits must NOT translate to an ARS destination. The local cluster element CEID digits are automatically inserted into the MiVoice Business dial plan similar to a local telephone DN. See also ARS Digits Dialed (Conditions section) for additional information.

Digits Dialed | Number of Digits to Follow | Termination Type | Termination Number
7167 | +4 | Route | 7
7167YYYY | +0 | List | 5
7167NXY | + unknown | Plan | 2

As a further example, the following ARS entries will NOT satisfy the requirement:

Digits Dialed | Number of Digits to Follow | Termination Type | Termination Number
7 | +7 | Route | 7
71YYYYYY | +0 | List | 5
7167NXY5 | + unknown | Plan | 2

The Cluster Elements form is divided into two sections:

- Cluster Elements (top section): provides a "Create Cluster" button that allows you to create a cluster to which to add elements. After a cluster has been created, this section of the form will allow you to change the name and PNI of the cluster.

- Cluster Members information (lower section): allows you to modify an existing cluster. You can Add Member, Change Member (a page at a time or all at once), or Delete Member.

### ARS Wild Cards

ARS wild cards can be used in clustered environments, to replace explicitly-defined CEID trailing digits. For example, any of the following ARS rules can be used to define routes involving CEIDs in the ARS Digits Dialed form:

Digits Dialed | Number of Digits to Follow | Termination Type | Termination Number
167 | 3 | Route | 4
167NXYNXY | 3 | Route | 5
167NNNNN | Unknown | Route | 9

Use this form when performing the following tasks:

- Adding Cluster Elements (for System Data Synchronization)

- Data Sharing in a Multi-Clustered Network (for System Data Synchronization)

For more information:

- About System Data Synchronization

- System Data Synchronization Programming Overview

## Conditions

- You can only add cluster elements to a cluster that has already been created.

- If you are creating a new cluster, the local network element is added to the new cluster by default. You cannot create a cluster without including the local element in that cluster.

- If a cluster already exists, a second cluster cannot be created if some of the data-sharing network elements are of "MSL Server" type. These network elements do not support multiple clusters.

- After modifying the PNI of a cluster, you must wait at least 15 minutes before you perform a sync operation; otherwise, the sync operation may fail.

## Field Descriptions

Parameter | Description | Default Value
Cluster Elements
Name | Enter a unique name of up to 128 characters for the cluster. | Blank
Primary Node ID (PNI) | Enter a Primary Node ID for the cluster of up to 7 digits in length if the cluster is connected in a MSDN/DPNSS network. If the cluster does not belong to a MSNN/DPNSS network, a Primary Node ID is not required. The Primary Node ID is used to route calls to other non-cluster elements in the network. Clustered elements must share the same PNI. A PNI cannot appear as a directory number or as an ARS string on any of the systems in the network. Use the Locate Number maintenance command to determine if the PNI is a number that is already used on any of the other elements in the network. This value also appears in the primary Directory Number (DN) field of the ARS Node Identities form. NOTE: A confirmation dialog displays for a PNI change if the PNI change will be distributed to other cluster members via the System Data Synchronization feature. | Blank
Cluster Members
Choose an existing non-clustered network element: | Select an existing network element to add it to the cluster. Only elements previously entered in the Network Elements form that are not already members of a cluster appear in this list. | Blank
Name | Enter the name of the cluster element (maximum nine characters) or choose it from the list of non-clustered elements previously programmed in the Network Elements. A name is optional. If entered, the name is automatically added to the Network Elements form. NOTE: The name must be identical to the element name entered in MiVoice Enterprise Manager. Otherwise, attempts by Enterprise Manager to program resilient data on the secondary controller will fail. | Blank
PBX Number/Cluster Element ID | System-generated field. The unique identifier assigned to the element in the Network Elements form. | Blank
Cluster Element ID Digits | Enter a CEID digit string. Assign unique CEID digit strings to each cluster element. In a network that is configured for the Voice Clustering (Portable Directory Number) feature, the CEID digit string allows calls to be routed between elements in the network. The CEID digit strings for remote elements must translate to a programmed ARS route, list, or plan for correct call routing. NOTE: For the cluster element designated as "Local", the CEID digits must NOT translate to an ARS destination. The local cluster element CEID digits are automatically inserted into the MiVoice Business dial plan similar to a local telephone DN. See also ARS Digits Dialed (Conditions section) for additional information. The CEID digit string can be 1 to 7 digits in length. If the ARS digits are not yet assigned, the field displays "Not assigned". NOTE: If you enter a CEID digit string, you must enter a corresponding CEID index before you can commit the form. Having remote CEID digit strings translate to at least one ARS route, route list, or plan with identical leading digits is recommended. By having identical leading digits you minimize the risk of dialing conflicts that result when CEID digits match a local DN, but requires that you program an explicit ARS entry for every node in the cluster. NOTES To facilitate the configuration of a large multi-hub cluster which uses transit nodes to route calls between nodes in the hubs, any digit string is allowed provided that it translates to a valid ARS route, route list, or route plan. This allows you to use ARS entries containing wildcards for cluster routing. For example, for three remote nodes with CEID digits 1#100, 1#200, and 1#300, all calls can be routed to the transit node (1#100) by the ARS entry 1# with unknown digits to follow. ARS routing digits for all cluster elements must be the same length for resiliency to work. | Blank
Local | Select "Yes" to assign the adjacent CEID digit string to the local element (the system that you are currently programming). You can only designate one CEID digit string to the local element. The CEID digit string of the local element is added to the system number plan and must therefore be a unique directory number. Select "No" for the remote elements. | No
Feature DN | For the local element ("Local" is set to "Yes") enter a feature directory number. For a remote element, enter the feature directory number that corresponds to the local feature directory number of the remote element within the cluster. The local and remote feature directory numbers must be unique within the cluster and can be 1 to 7 digits in length. The directory number length must match the extension number length. NOTES This field allows DPNSS features such as busy lamp field messaging, direct paging, group page, and call pickup to function across the cluster. Do not use # or * in the Feature DN number because they can cause networking problems between the elements. If you leave this field blank, a negotiation failure may cause a virtual channel to be busied out every 20 seconds. When all virtual channels are busy, no IP trunks can be established with the indication of "XNET Busy". | Blank
Comments | Enter comments up to 20 characters. (Optional). | Blank