1531-DBC 422 02 Uen B3 2013-12-02
48
I
NSTALLATION
7.16 HLR
Redundancy
HLR redundancy is a function in the MX-ONE TSE system. If the Line
Interface Module (LIM), where the data for the extension (Home Loca-
tion Register) is stored, becomes unreachable, a temporary HLR will be
created in another LIM and the IP extension can register towards this
LIM.
The functionality of HLR Redundancy is different dependent on which
mode the phone is used in.
7.16.1 HLR
Redundancy in H.323
The information in this part is valid for H.323.
7.16.1.1 Prerequisites
The HLR redundancy feature will only work when:
•
Automatic gatekeeper discovery (with multicast) is
not
used
•
The gatekeeper address is
not
set manually
•
Backup gatekeeper is
not
used (in branch office scenarios)
•
In the configuration file of the phone, both primary and secondary
gatekeeper (GK) address must be defined.
7.16.1.2
Change-over to Temporary HLR
The phone will use the primary GK address towards the entry GK in
MX-ONE, and receive a list of the GKs to be used. Alternatively the entry
GK could accept the registration directly. If a list is received, the phone
will try to register according to the list.
When the server (LIM) with the ordinary HLR becomes inaccessible,
there are two different cases:
•
The phone was registered in the LIM of the ordinary HLR. The
terminal will not receive any reply to the keep-alive check and will
then try re-registration to the secondary GK, according to the
configuration file. A temporary HLR will be created in the LIM where
the registration can be accepted.
•
The phone was registered in another LIM than in the ordinary HLR
LIM. This will happen if load distribution was used when trying to
register to the primary GK. A temporary HLR will be created in that
other LIM (where the phone was registered).
