Endpoint Manager (EPM) boot process - please explain

We’ve configured our Snom phones to use Endpoint Manager. This is a very cool product at 10x the price. Could someone explain the inner workings of the /tftpboot directory files, though?

When the phone (Snom, for example) boots, what file is it looking for first? Then what comes next?
What takes priority? DHCP option 66 TFTP server address or the Snom’s configured Update address?
In the Option 66, must I prefix with the protocol (e.g. tftp://…)? I think not, based on Snom’s documentation

This will help us troubleshoot the boot process using Endpoint Manager.

Change the following file to include the -vvv option on the server_args -

[[email protected] xinetd.d]$ cat /etc/xinetd.d/tftp 
# default: off
# description: The tftp server serves files using the trivial file transfer \
#	protocol.  The tftp protocol is often used to boot diskless \
#	workstations, download configuration files to network-aware printers, \
#	and to start the installation process for some operating systems.
service tftp
	disable	= no
	socket_type		= dgram
	protocol		= udp
	wait			= yes
	user			= root
	server			= /usr/sbin/in.tftpd
	server_args		= -s /tftpboot -vvv
	per_source		= 11
	cps			= 100 2
	flags			= IPv4

Sorry, I don’t recall if I had to restart xinetd or not after making the change.

Then you can watch /var/log/messages for the tftp activities.

Each manufacturer has its own priorities and setups.

If my memory serves me right, Snom will ignore option 66 if a provision address is specified in the gui. If you specify the address you should only need the “tftp://” if there is not a select box for what protocol to use. ie: if you have to select the provision server as tftp, you don’t need the tftp://

Whether by option 66 or defined provisioning, Snom’s look for the following files:
snom-{templatename}-S-{model}.xml (for images only)