Mitel Deutschland GmbH 68635RFP36U-01 ユーザーズマニュアル
SIP-DECT OM System Manual
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With these states (“… SIP inactive”) the OMM standby mechanism takes care in the start up phase that
all SIP users does not become active if the PBX is not reachable. This avoids a possible double SIP
registration when the PBX and the other OMM is reachable again before both OMMs negotiate which
OMM becomes the active one.
all SIP users does not become active if the PBX is not reachable. This avoids a possible double SIP
registration when the PBX and the other OMM is reachable again before both OMMs negotiate which
OMM becomes the active one.
The double SIP registrations might cause a user not to be reachable when his latest SIP registration
came from that OMM that was negotiated to be the inactive one and the SIP registrar cannot handle two
or more simultaneous registrations (non-forking proxy).
came from that OMM that was negotiated to be the inactive one and the SIP registrar cannot handle two
or more simultaneous registrations (non-forking proxy).
Similarly, it could happen in rare cases that both OMMs become temporarily active. In such a situation all
SIP-DECT users would be SIP registered from both OMMs to the configured PBX. This can cause
problems, if the PBX accepts only one registration per user (non-forking proxy).
SIP-DECT users would be SIP registered from both OMMs to the configured PBX. This can cause
problems, if the PBX accepts only one registration per user (non-forking proxy).
To prevent such problems a mechanism is implemented to detect situations with two active OMMs. If
such a situation is detected the remaining active OMM SIP re-registers all users to the PBX if the OMM
SIP reRegister after 2 active OMM failover parameter is set (see section 5.4.3.6).
such a situation is detected the remaining active OMM SIP re-registers all users to the PBX if the OMM
SIP reRegister after 2 active OMM failover parameter is set (see section 5.4.3.6).
7.15.4 SPECIFIC STANDBY SITUATIONS
Some aspects must be described in case of OMM state changes when they are unsynchronized.
7.15.4.1 How a standby OMM becomes active
In an unsynchronized OMM state, the standby OMM must decide whether to become active or not.
In an unsynchronized OMM state, the standby OMM must decide whether to become active or not.
The OMM tries to contact the configured SIP proxy and registrar. If a specific user account has not been
designated to use for visibility checks (see section 7.20.7), the OMM starts a SIP registration for the
DECT phone with the lowest phone number and sends an OPTIONS request to the configured proxy. If
there is an answer the SIP proxy/registrar is considered reachable and the OMM becomes active.
designated to use for visibility checks (see section 7.20.7), the OMM starts a SIP registration for the
DECT phone with the lowest phone number and sends an OPTIONS request to the configured proxy. If
there is an answer the SIP proxy/registrar is considered reachable and the OMM becomes active.
7.15.4.2 When OMMs are not synchronized
In an unsynchronized OMM Standby state, the connection between the OMMs is broken. In case of a
network problem, both OMMs might be in this state. During this time an inconsistent OpenMobility
system is operational with some constraints.
In an unsynchronized OMM Standby state, the connection between the OMMs is broken. In case of a
network problem, both OMMs might be in this state. During this time an inconsistent OpenMobility
system is operational with some constraints.
The OMM Web service issues a warning with the message “No Standby” for both OMMs and it is
possible that configuration changes made are not saved.
possible that configuration changes made are not saved.
When both OMMs are in contact again, the longer running OMM becomes the active OMM and
overwrites the database file in the standby OMM. Configuration changes made in this OMM instance are
lost.
overwrites the database file in the standby OMM. Configuration changes made in this OMM instance are
lost.
7.15.4.3 Two DECT air interfaces
When both OMMs are in an unsynchronized and active state, they are fully operational. DECT base
stations that lose their connection to the OMM because of a network outage might connect to the other
OMM. Two DECT air interfaces are present and work in parallel.
When both OMMs are in an unsynchronized and active state, they are fully operational. DECT base
stations that lose their connection to the OMM because of a network outage might connect to the other
OMM. Two DECT air interfaces are present and work in parallel.
Note: Since both air interfaces use the same PARK, it is impossible to
determine on which OMM a location registration succeeds.
For DECT phones different situations are possible:
•
They do not notice this situation: