Servers in a replication realm must comply with the following requirements.
All servers in a replication realm must be running the same operating system version and patches.
All servers in a replication realm must be running the same version of SBR Carrier.
All servers in a replication realm must be configured to support the same types of users (host or UNIX).
The system clocks on servers in a replication realm must be synchronized to within 10 minutes of one another and their time zones must be configured correctly. SBR Carrier uses the system clock value and time zone setting to convert local time to Universal Time Coordinated (also known as Greenwich Mean Time) when evaluating synchronization. If possible, use a Network Time Protocol (NTP) server to set the system clock on all servers automatically.
All servers in a replication realm must use the same TCP port to exchange replication information. The default port for replication communication is TCP 1812, though you can specify another port for replication traffic by modifying the radius.ini file.
If a firewall stands between servers in a replication realm, the firewall must be configured to pass traffic on the port used for replication communication.