This article provides an overview of the Avaya IP Phone registration procedure (for UNIStim IP Phones)

When the phone is powered up, the following happens:
- NVRAM (non-volatile RA) is loaded, including the local configuration information. Any configuration options set to manual on the phone will overwrite automatic configuration information received.
NOTE If you experience any problems with any part of the process, use the IP Phone Factory Default reset procedure to clear all local configuration settings. - Phone then boots and determines if data switch provides LLDP or ADAC. This setting can be disabled manually, via DHCP or via manual provisioning. Unless this is disabled manually, the phone will always check LLDP/ADAC when it first boots.
NOTE Leaving LLDP/ADAC enabled when it is not supported by the Layer 2 switching equipment installed at the site can extend boot times for IP Phone devices. While LLDP/ADAC is enabled in a factory default configuration, it is recommended that this be disabled unless it is specifically supported by the networking environment. - The phone then requests DHCP. If DHCP is available it processes the DHCP information.
- If a provisioning server is provided via DHCP Option 66, DHCP or manually configured on the IP Phone, then the the IP Phone requests the system.prv and <TYPE>.cfg from the HTTP or TFTP servers. While there is a lot more available under manual provisioning than just firmware upgrades (and while I will be writing an article to cover those topics later), I have only written the manual firmware upgrade article.
- Then the phone attempts to contact the S1 and S2 (primary signaling server and failover signaling server). If the phone cannot make a connection to the signaling server (or that information isn’t provided via any of the configuration methods available: manual, DHCP or provisioning server) then the Phone reboots and tries again.
- If a connection is made to either the primary or failover signaling server, then the phone will register and proceed with attempting to connect to External Application Servers (XAS) such as the Application Server 1000. A lot of the functionality that was originally relegated to an External Server (screen savers, backgrounds, some directory functions) have been incorporated in to the base firmware/functionality of the IP Phones. Others still require an XAS. For more information on this, contact an authorized Avaya distributor.
The only information that is critical to an IP phone for the boot process is:
- Set IP address, subnet mask and gateway
- Primary signaling server (S1) IP address, Port, Action and Retry values
- Node and TN
When troubleshooting, eliminate variables by resetting the unit back to factory default and then configure only the minimum number of settings needed to establish connectivity (start with manually configuring the phone, then migrate components of the configuration back to auto to determine where the process fails.)
There are several reasons why you might want to enable manual provisioning of your Avaya IP Phones:
When troubleshooting QOS issues (including dropped calls, one way talk path, etc.) on an Avaya CS1000, sometimes it’s helpful to look at all of the alarms (even the unnacceptable or warning alarms) on a per-call basis. This gives you an idea of when there are problems in an entire zone vs individual users within the zone, or zone-wide and ongoing versus intermittant and individualized alarming.
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