AASTRA SIP-DECT (Release 2.1)- OM System Manual - Installation, Administration and Maintenance EN - Manual (Page 152)

SIP – DECT OM System Manual Release 2.1 7 Configuration und Administration Aspects
depl-1230/1.3 Page: 152 (196)
PBX not reachable
(registration and OPTIONS
request failes)
OMM sync NOK and
PBX unreachable
In this state the DECT air interface might not be in a definite
state, when both OMMs are active but do not see each other!
In this case a network problem occurs (broken into two parts)
which is very theoretical and we can not handle. There might
be two DECT systems with the same PARK active. For this
case it is random which RFP is connected to the one or to the
other OMM.
In this state hand over might be reduced (not all RFPs might
be synchronised).
OMM sync OK
Another OMM is running
for a longer period
OMM sync OK
OMM sync NOK
OMM Start up
or Restart
Synchronised
Inactive OMM
OMM star up sync
OK
Unsynchronised
Inactive OMM
OMM sync NOK and
PBX reachable
OMM sync OK
other OMM is active
OMM sync NOK
Synchronised
Active OMM
Unsynchronised
Active OMM
No OMM is active and
I have the lowest IP address
OMM sync OK
only one OMM is active
PBX not reachable
(registration and
OPTIONS request
failes)
PBX reachable
(registration or OPTIONS
request OK)
„OMM sync OK“ means: OMMs are synchronised with each other and are able to exchange their operational states
„OMM sync NOK“ means: OMMs are not synchronised with each other and are not able to exchange their operational states
OMM – Reset with exit code 45 OMM – Reset with exit code 46
7.11.4 Specific Standby Situations
Some aspects have to looked at in case of OMM state changes when they are
unsynchronized.
7.11.4.1 How A Standby OMM Becomes Active
As the above figure shows in case of an unsynchronized OMM state the standby OMM has
to decide whether to become active or not.
For this purpose the OMM tries to contact the configured SIP proxy and registrar. The OMM
starts a SIP registration for the handset with the lowest phone number and sends an
OPTIONS request to the configured proxy. If there is an answer the SIP proxy/registrar will
be considered as reachable and the OMM becomes active.
7.11.4.2 Handling When Both 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 working with some constraints.
The Web service will warn with the warning “No Standby” for both OMMs in this situation and
possible made configuration changes are not save.