Operating instructions

the same on both units).
The IP address that the peer has configured for "Peer IP Address". For a valid
configuration the "Peer IP Address" setting on the other unit should refer to this unit's
control IP address.
Hardware configuration and software version numbers are also compared. If these do not
match an alarm is raised, although the units continue to pair.
If during the pairing process the peer unit cannot be successfully pinged for 30 seconds,
then it is assumed that the peer is not available. In this case the unit will become Active.
Once a successful configuration has been established, the Active unit will be determined. For
this the current Active state and the previous Active state are used. If the unit has just been
powered up, the current active state will be Passive.
If one of the units is Active and the other is Passive then the Active unit remains Active
and the Passive unit remains Passive. The configuration of the Active unit is copied to
the Passive unit.
If both of the units are Active then the "Conflicting Status" alarm is raised, and both
units remain Active. A "Configuration Mismatch" alarm is also raised to indicate that
the configuration of the 2 units could not be synchronised automatically.
If both of the units are Passive then the previous state is examined.
If one unit was previously Active and the other unit was previously Passive, then
the previously Active unit becomes Active, the previously Passive unit remains
Passive, and the configuration is copied from the previously Active unit to the
previously Passive unit.
If both units were previously Active or both units were previously Passive, then
the "Conflicting Status" alarm is raised, and both units remain Passive. A
"Configuration Mismatch" alarm is also raised to indicate that the configuration of
the 2 units could not be synchronised automatically.
Automatic Redundancy Switching
Under certain circumstances an automatic redundancy switch will take place. Normally
automatic redundancy switches will only occur if the Primary unit is Active (i.e. there is no
auto-revert back from Secondary the Primary). The exception to this is when the timed
license on the Secondary unit expires.
When the Primary is Active an automatic redundancy switch will occur when:
A critical alarm is present on the Primary and no critical alarm is present on the
Secondary for more than the time specified by "Alarm Primary to Secondary Delay"
The Secondary is unable to ping the Primary for more than the time specified by "Ping
Primary to Secondary Delay"
When the Secondary is Active an automatic redundancy switch will occur when:
The Secondary timed license expires
Configuration Synchronisation
When configuration changes are made to one unit in a redundancy group they are
automatically replicated to the other unit. The GUI of the other unit should be reloaded to
see any changes made. This occurs for most parameters, although a few so called "Box
Parameters" are unique to a unit and are not replicated. Examples of parameters that are