Synchronizing Configurations

You can synchronize the Oracle Communications Session Border Controllers (OCSBC) in your High Availability (HA) node in the following ways:

Automatically — Set up configuration checkpointing within the HA node.
Manually — Check whether or not configurations in the HA node are synchronized, and then copy configuration data from one OCSBC to the other.

When you initially configure a new HA node, copy the configuration data manually from one OCSBC to the other. When you complete the process, you can configure your HA node to automatically synchronize configurations.

Oracle recommends that you configure the HA node for configuration checkpointing because that is the most reliable way to ensure that both systems have the same configuration.

Synchronize HA Peers

The process for synchronizing the peers in a High Availability (HA) node for the first time by way of the ACLI includes the following steps.

Create a complete configuration on the active Oracle Communications Session Border Controller (OCSBC). Include all HA node parameters and all rear interface configurations. Confirm that the rear interfaces are configured to send and receive information across the HA node.
On the active OCSBC, save the configuration.
On the active OCSBC, reboot to run the new configuration.

Use the ACLI show health command to see that the active OCSBC booted without a peer. This changes after you copy the configuration to the standby OCSBC and activate the configuration.
On the standby OCSBC, perform the ACLI acquire-config command to copy the configuration from the active OCSBC. Use the acquire-config command with the IPv4 address of wancom 0 on the active OCSBC.
```
ACMEPACKET2# acquire-config 192.168.12.4
```
The IPv4 address of wancom 0 on the active OCSBC is the IPv4 address portion of the value displayed for the IP Address boot parameter. The following codeblock shows an example of theIP Address value that the system displays when you view the boot parameters:
```
IP Address        : 192.168.12.4
```
When the copying process (acquire-config) is complete, reboot the standby OCSBC to activate the configuration. The system boots and displays start-up information.

Confirm that the HA node synchronized the configurations by using the ACLI display-current-cfg-version and display-running-cfg-version commands:

ORACLE# display-current-cfg-version
Current configuration version is 3
ORACLE# display-running-cfg-version
Running configuration version is 3
ORACLE# display-current-cfg-version
Current configuration version is 3
ORACLE# display-running-cfg-version
Running configuration version is 3

In the preceding example, all configuration versions—current and running—are the same number (3).

RTP Timestamp Synchronization

The Oracle Communications Session Border Controller maintains the continuity of egress transcoded media streams during HA switchover by synchronizing the RTP timestamps between active and standby systems.

For a new call, the transcoding resources are allocated and each session is configured with an initial RTP timestamp value. This process is repeated independently on both the active and standby systems to maintain approximately the same timestamps. This minimizes the difference between active and standby-side interpretation of the current RTP timestamp for a new session.

During HA operation, the active system maintains new timers that check for transcoded sessions lasting fifteen minutes or more. The active system re-synchronizes the RTP timestamp after fifteen minutes. This prevents the RTP timestamps from drifting due to clocking differences between active and standby hardware.

In addition, when the standby system boots, it performs a complete session sync with the active system for all currently active sessions.

Using Configuration Checkpointing

The Oracle Communications Session Border Controller’s primary and secondary utility addresses support configuration checkpointing, allowing the standby Oracle Communications Session Border Controller to learn configuration changes from the active Oracle Communications Session Border Controller. This means that you only have to enter configuration changes on the active Oracle Communications Session Border Controller for the configurations across the HA node to be updated.

Configuration checkpointing uses parameters in the network interface and in the Oracle Communications Session Border Controller HA Nodes/redundancy configurations.

If you are using configuration checkpointing, you also need to set up two Oracle Communications Session Border Controller peer configurations: one the primary, and one for the secondary.

HA Configuration Checkpointing

You need to first set applicable network interface configuration parameters, and then establish applicable parameters in the Oracle Communications Session Border Controller HA node (redundancy) configuration.

We recommend that you do not change the configuration checkpointing parameters in the redundancy configuration. Using the defaults, this feature will function as designed.

Note:

Remember to set the appropriate type parameter in the HA node redundancy peers configuration.

For the network interface, these parameters appear as they do in the following example when you use the ACLI. This example has been shortened for the sake of brevity.

pri-utility-addr               169.254.1.1
sec-utility-addr               169.254.1.2

For the Oracle Communications Session Border Controller HA node (redundancy) configuration, these parameters appear as they do in the following example when you use the ACLI. This example has been shortened for the sake of brevity. You should not change these values without consultation from Oracle Technical Support or your Oracle Systems Engineer.

cfg-port                       1987
cfg-max-trans                  10000
cfg-sync-start-time            5000
cfg-sync-comp-time             1000

To configure HA configuration checkpointing in the ACLI:

In Superuser mode, type configure terminal and press Enter.
```
ORACLE# configure terminal
```
Type system and press Enter to access the system-level configuration elements.
```
ORACLE(configure)# system
```
Type network-interface and press Enter. The system prompt changes to let you know that you can begin configuring individual parameters.
```
ORACLE(system)# network-interface
ORACLE(network-interface)#
```
From here, you can configure network interface parameters. To view all network interfaces parameters, enter a ? at the system prompt.
pri-utility-addr—Enter the utility IP address for the primary HA peer in an HA architecture.

This address can be any unused IP address within the subnet defined for the network interface. For example, given a network interface of with the IPv4 address 168.0.4.15/24 (identifying the host associated with the network interface), the possible range of unused IPv4 addresses is 168.0.4.1 to 168.0.4.254. Your network administrator will know which IPv4 addresses are available for use.
sec-utility-addr—Enter the utility IP address for the secondary Oracle Communications Session Border Controller peer in an HA architecture.

Usually, this IP address is usually the next in the sequence up from the primary utility address. It is also generated from the range of unused IP addresses within the subnet defined for the network interface.

Save your work and exit the network interface configuration.

ORACLE(network-interface)# done
ORACLE(network-interface)# exit
ORACLE(system)#

Access the system HA node/redundancy configuration by typing redundancy at the system prompt and then press Enter.
```
ORACLE(system)# redundancy
ORACLE(redundancy)#
```
Note:
We strongly recommend that you keep the default settings for the parameters Steps 8 through 11.
cfg-port—Enter the port number for sending and receiving configuration checkpointing messages. Setting this to zero (0) disables configuration checkpointing. The default value is 1987. The valid values are:
- Minimum—0, 1025
- Maximum—65535
cfg-max-trans—Enter the number of HA configuration checkpointing transactions that you want to store. The active Oracle Communications Session Border Controller maintains the transaction list, which is acquired by the standby Oracle Communications Session Border Controller. Then the standby system uses the list to synchronize its configuration with active system. The default value is 10000. The valid range is:
- Minimum—0
- Maximum—4294967295
  
  Transactions include: modifications, additions, and deletions. If the maximum number of stored transactions is reached, the oldest transactions will be deleted as new transactions are added.
cfg-sync-start-time—Enter the number of milliseconds before the Oracle Communications Session Border Controller tries to synchronize by using configuration checkpointing. On the active Oracle Communications Session Border Controller, this timer is continually reset as the Oracle Communications Session Border Controller checks to see that it is still in the active role. If it becomes standby, it waits this amount of time before it tries to synchronize.

We recommend you leave this field at its default value, 5000, so that configuration checkpointing can function correctly. The valid range is:
- Minimum—0
- Maximum—4294967295
cfg-sync-comp-time—Enter the number of milliseconds that the standby Oracle Communications Session Border Controller waits before checkpointing to obtain configuration transaction information after the initial checkpointing process is complete.

We recommend you leave this field at its default value, 1000, so that configuration checkpointing can function correctly. The valid range is:
- Minimum—0
- Maximum—4294967295

Save your work and exit the redundancy configuration.

ORACLE(redundancy)# done
ORACLE(redundancy)# exit
ORACLE(system)#

Manually Checking Configuration Synchronization

You can check that the current and active configurations are synchronized across the HA node. The current configuration is the one with which you are currently working, and the active configuration is the one active on the system.

To confirm that the systems in the HA node have synchronized configurations:

On the active Oracle Communications Session Border Controller in the Superuser menu, enter the following ALCI commands and press Enter. Note the configuration version numbers for comparison with those on the standby Oracle Communications Session Border Controller.
- display-current-cfg-version—Shows the version number of the configuration you are currently viewing (for editing, updating, etc.).
```
ORACLE# display-current-cfg-version
Current configuration version is 30
```
- display-running-cfg-version—Shows the version number of the active configuration running on the Oracle Communications Session Border Controller.
```
ORACLE# display-running-cfg-version
Running configuration version is 30
```
On the standby Oracle Communications Session Border Controller, enter the following ALCI commands and press Enter. Note the configuration version numbers for comparison with those on the active Oracle Communications Session Border Controller.
```
ORACLE# display-current-cfg-version
Current configuration version is 30
ORACLE# display-running-cfg-version
Running configuration version is 30
```
Compare the configuration numbers. If the version numbers on the active Oracle Communications Session Border Controller match those on the standby Oracle Communications Session Border Controller, then the systems are synchronized.

If the version numbers do not match, you need to synchronize the Oracle Communications Session Border Controllers. You can do so using the ACLI acquire-config command.