Sep 192013
 

LLDP-MED for Avaya CS1000 IP PhonesIncreasing boot efficiency is one of those things I’m working on. My personal or work PC, my IP Phone, systems I manage. The less time I have to spend sitting around waiting for something to boot up is more time doing something productive. On the PC, that involves looking at your startup folder, your registry run folders and removing any unnecessary services from automatic startup.

For Avaya CS1000 IP Phones, that involves looking at the config and determining which features can be added or removed to achieve an optimal boot up sequence.

Although my 4st post is not live yet (when it is, it will be here), in it I cover Link Layer Discovery Protocol (LLDP) and how it applies to Avaya CS1000 IP Phone deployment. On of the biggest inefficiencies I’ve found in CS1000 IP Phone deployments is where customers leave LLDP enabled but don’t use it.

ZzzWaiting for LLDP-MED (Link Layer Discovery Protocol, Media Endpoint Discovery) can add as much as 30 seconds delay to the boot process… So disable it if you’re not using it!

With stickiness, you can configure the Phone to not use LLDP on bootup, or you can disable it manually at each phone by turning it off.

On the other hand, if use LLDP you might increase boot efficiency by distributing the configuration of the IP Phones and reducing dependency upon DHCP. If you want to configure the Voice VLAN but don’t use LLDP, your options are to manually configure each IP Phone or use the VLAN-A option to assign a Voice VLAN ID.

Avaya CS1000 IP Phone, DHCP provisioning behaviorIf you use DHCP though, you’re going to be querying the DHCP server (or multiple servers) multiple times.

It’s certainly faster than waiting for LLDP-MED to time out, but using LLDP-MED is faster than multiple DHCP queries (Although talking a fraction of the delay caused by LLDP-MED being enabled and unused.)

It’s also a good idea to reduce the number of retries to allow the IP Phone to failover to an alternate signaling server (i.e. Connect Server) more quickly.

Take away:

  • If you’re not using a feature, disable it. Your phones will boot faster and you’ll recover more quickly from maintenance windows or disaster.
  • Nortel-i2004-B,s1ip=10.10.10.10;p1=4100;a1=1;r1=3;s2ip=10.10.10.20;p2=4100;a2=1;r2=3;vq=y;st=y;lldp=n;vvsource=a;

Jan 232012
 

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:

  1. 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.

     

  2. 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.

     

  3. The phone then requests DHCP. If DHCP is available it processes the DHCP information.
  4. 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.
  5. 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.
  6. 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:

  1. Set IP address, subnet mask and gateway
  2. Primary signaling server (S1) IP address, Port, Action and Retry values
  3. 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.)