Network design notes for the Split Registration Prevention feature

Last Updated : Jul 17, 2023 |

Ensure that you fulfill the following requirements when you administer split registration prevention:

  • Run the disable nr-registration command in a region that has gateways. The survivable server becomes active when a gateway registers itself to the server. The main server deactivates all regions backed up by the survivable server.

  • If the survivable server associated with the region is active, run the enable nr-registration command to auto disable the network region.

  • You cannot use the enable nr-registration command to activate a network region that is automatically deactivated by the Split Registration Prevention feature.

  • All gateways must have trunks and VoIP resources. The branch gateways registered to the survivable server that do not have trunks and VoIP resources are the only ones registered to a survivable server.

  • If the processor Ethernet addresses of survivable server are listed in a telephone Alternate Gatekeeper List (AGL) or Media Gateway Controller (MGC) list, split registrations might occur between the main server and the survivable server. If a telephone registers to a PROCR of survivable server, the telephone can make calls with the trunk.

  • When administering the MGC list of a media gateway, the part of the list after the survivable server transition point must contain only one entry administered under the BACKUP SERVERS heading of the Media Gateway region on the IP Network Region screen.

  • If the corresponding survivable server is currently registered and active, you cannot change a survivable server entry under the column heading BACKUP SERVERS IN PRIORITY ORDER.

  • All gateways in a single network region using time-day-window media recovery rules must follow the same rule. Any variation to the recovery rules creates confusion about further events.

  • The AGL that IP telephones receive after they reboot must contain the address of the survivable server at the end of the list. If the IP address of the survivable server is not listed in AGL and the main server is unreachable, telephones cannot register with the survivable server.