INTRODUCTION

The 1+N media cluster feature allows clustering multiple devices from the UCM630x and GCC602x series to expand the number of concurrent calls and meeting participants.

The deployment architecture of this feature consists of one main business server that handles signaling, and at least one other server handling the media traffic. Please see the example for the UCM630x series below.

CONFIGURATION STEPS

The configuration of the cluster feature consists of two main parts, one part will be about the configuration of the business server, and the other part will be about the configuration of the media server(s).

Business Server

Setting a Static IP address

To ensure that the connection isn’t lost to the business server, the user must configure a static IP on the business server.

• For UCM630x devices:

A static IP can be configured directly in the web UI or reserved on the DHCP server.

1. Access the web UI, navigate to System Settings → Network Settings, and then set a static IP on the network interface which is connected to the network where the media servers are hosted.

2. Click “Save” to save the configuration.

• For GCC602x devices:

A static IP can only be set when enabling the PBX module. After the PBX module is enabled, the IP cannot be modified directly. To change it, the PBX module must be disabled and re-enabled. The previous configuration remains intact after re-enabling.

Configuring the Cluster Settings

To configure the UCM/GCC device as the Business Server, please follow the steps below:

1. Navigate to System Settings → Cluster, then tick the option Enable Media Cluster.
2. Choose “Business Server” as the Device Role.
3. Choose the Multicast Network Port. This depends on the networking settings of the device (Route mode or Dual mode).
4. Enter a Multicast IP address that will be used to send multicast traffic. Please ensure the IP address is within the allowed multicast range (224.0.1.0 – 238.255.255.255).
5. Enter a port range start value and end value in the corresponding fields. The range must be between 1024 – 65535.
6. Enter the Business Server Listening Port number. This must also be within 1024 – 65535.
7. Enter the Media Server addresses. These can be added in advance and later assigned to the media server(s).
8. Once all settings are entered, click “Save” to save the configuration.

Media Server

Setting static IP address

Similar to the business server, we also need to set the static IP address for the media server to avoid losing the connection to it.

• For UCM630x devices:

A static IP can be configured directly in the web UI or reserved on the DHCP server.

1. Access the UCM’s web UI, navigate to System Settings → Network Settings, and then set a static IP on the network interface which is connected to the network where the business server is hosted.

2. Click “Save” to save the configuration.

• For GCC602x devices:

A static IP can only be set when enabling the PBX module. After the PBX module is enabled, the IP cannot be modified directly. To change it, the PBX module must be disabled and re-enabled. The previous configuration remains intact after re-enabling.

Configuring the Cluster Settings

To configure the GCC/UCM device as a media server, please follow the steps below:

1. Please navigate to System Settings → Cluster
2. Tick the option “Enable Media Cluster”
3. Select “Media Server” as the Device Role
4. Enter the IP address of the business server and the listening port configured on the Business server.

5. Then click “Save” to save the configuration.

CONSIDERATIONS

Some of the settings which are important for the normal operation of the cluster are synchronized automatically; meeting settings and RTP ToS settings are synchronized automatically. Meanwhile the NAT traversal settings such as TURN server address, STUN server address etc… are only sychronized if “Sync Media NAT Traversal Settings” option is enabled, please see [Business Server] section.

Meeting Settings

For media servers, all the configuration options on this page are greyed out to display the information configured on the business server.

SIP Settings

Please ensure that the following ToS SIP settings are identical across all the devices that are involved in the cluster. To access the configuration page please navigate to PBX Settings → SIP Settings → ToS

RTP Settings

If the Business Server is behind a NAT router and does not have a RemoteConnect plan, port forwarding must be configured on the router. Each media server, whether UCM or GCC, should use a unique port range for RTP and BFCP. For example:

• UCM1: 10000–20000
• UCM2: 20001–30000
• UCM3: 30001–40000
• GCC servers follow the same rule with their own ranges.

The same logic applies to BFCP. Port forwarding rules should map each range to the corresponding server’s IP address. If a TURN server is used, it can serve all media servers.

To access the configuration page of RTP Settings, please navigate to PBX Settings → RTP Settings

The following media NAT Traversal parameters will only be visible on the business server:

The remaining settings will be greyed out on the media server’s side. Only the configuration on the business server will be taken into consideration.

CLUSTER CAPABILITIES

The following table mentions the number of calls each business server is capable of processing and the additional calls that each media server will process based on the model of the device used.

• Example:

If a UCM6304 acts as the business server and has an additional UCM6304 and UCM6308 as media servers, the capacity would be as follows:

• Concurrent Calls = 300 (UCM6304 Business Server) + 335 (UCM6304 Media Server) + 390 (UCM6308 Media Server) = 1025
• Meeting Participants = 200 (UCM6304 Business Server) + 250 (UCM6304 Media Server) + 300 (UCM6308 Media Server) = 750

Additionally, CPU thresholds can be set on each media server to restrict the number of calls based on CPU usage. For example, if a 90% CPU threshold is set on both media servers, the capacity calculation would become:

• Concurrent Calls = 300 + ((335 + 390)*0.90) = 952
• Meeting Participants = 200 + ((250 + 300)*0.90) = 695

HIGH AVAILABILITY WITH THE CLUSTER

Local Hot-standby:

If the business server is configured with HA Local Hot-standby, then the media server must configure the Business Server IP field with the HA cluster IP address. In case of HA failover, the secondary unit will also be able to take advantage of the existing media cluster.

Remote Disaster Recovery:

Cluster configuration is not synced in Remote Disaster Recovery environments. Users can choose to expand the capacity of only one of the UCMs or both units. In the case of the latter, the primary and secondary units must configure their own separate cluster environments.

SUPPORTED DEVICES