Avaya 1000 Installation And Commissioning Manual page 29

Figure 4: MO-GRMO-BO or PCS-SCS-SMG or GR N-way deployment
In this deployment, there is a limitation that the GRMO and BO system cannot be down at the same
time. At least one system must be up and running to facilitate redirection (since the purpose of
geographic redundancy is to handle network outage, not server failures). Single server failures must
be handled using the server redundancy feature. As a result, this limitation can be overcome by
implementing both server redundancy and geographic redundancy.
Scenario 1 (SIP client reset)
The SIP client is registering to the system for the first time. The BO system is down.
1. The SIP client sends a PING/REGISTER request to the GRMO SLG.
2. The GRMO SLG is aware that MO-SLG is up, so the GRMO SLG ignores the PING request.
3. The GRMO SLG responds with a 302 Moved Temporarily for the REGISTER request. The
contact header of this SIP message contains the redirection IP address (that is, the MO
SLG).
4. The SIP client redirects the REGISTER message to the MO SLG.
5. The MO SLG responds back with a 200 OK for the REGISTER request after the
authentication process.
6. The SIP client configures the MO SLG as its active proxy. After this configuration, incoming
requests are received from this active proxy and any outgoing responses are sent to this
active proxy.
June 2014
MO-GRMO-BO or PCS-SCS-SMG or GR N-way deployment
Branch Office Installation and Commissioning
Comments? infodev@avaya.com
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