Snom phones rely on provisioning server, essentially an http or https server that responds to a particular request with specific xml file(s), which are later applied to all phones or a particular one, thus managing settings, user account and so on. Before we go in to details about the format and the content of the provisioning files, we must answer perhaps the most important question – how Snom phone will “know” where to go to get the provisioning information?
Snom uses DHCP Option 66 (TFTP Server Name) to obtain information of the provisioning server URL. One question comes immediately to mind – “Ok… we are not booting from TFTP, why using this option in first place. And, I already use it for other devices on the network… am I doomed?”
My answer to the first question – I have no idea! Perhaps Snom ran out of “options”? My goal is, however, to show you an alternative way to utilize this option and have central management solution in place.
As many other well designed network devices, Snom endpoints will submit Option 60 (Vendor Class Identifier) in the in the DHCP Discovery broadcast. The goal is – if the DHCP server understands the option and the Scope/Server options are properly configured, the DHCP response will contain a very specific values meant for the requester (Snom) only. With other words, you could already have an Option 66 set for some purposes and still supply your Snom phones with unique value (namely “Provisioning URL”).
Before we precede with the configuration steps of our DHCP server, there are few important notes:
- Each Snom model submits the word “snom” (lower case!) and the model number in a single string i.e. snom300, snom320, snom360…snom870 and so on as “Vendor Class Identifier”. I got to think today - why not only “snom” so that we will have to configure the entire shebang one time only? Well, model 300 (with its simplicity), compared to 870 with the large color touch screen display, is like Ford Fiesta next to Cadillac Escalade. And… Snom 8xx series can show live stream (security camera for example) on the display… bottom line - different features require different provisioning options.
- This example is for Microsoft DHCP server. If you are Linux guy, the assumption is that you already “know it all” and/or your Ubuntu or SUSE or whatever makes you hot has configured itself already, fearing the possibility to face you… or Chuck Norris…
- The screenshots are from DHCP mmc on Windows 2008 R2
Right click on IPv4 and select “Define Vendor Classes”
In New Class window, populate as shown and click OK button.
Right click on IPv4 and select “Set Predefined Options”
Select snomXXX model and click Add
In Options Type windows, populate the fields as shown:
***by setting this prerequisites, we will send the provisioning URL via option 66, BUT encapsulated in Option 43 i.e. different way compared to DHCP Standard Option 66.
Now right click over the Scope Options (of the scope your phones are on) and select “Configure Options”.
***This part can be very tricky and need a little explanation. Notice that the box has three sections – Data, Binary, and ASCII.
- Don’t worry about Data, nor Binary (unless you hate your life)
- Click under ASCII (on right of the “.”
- Backspace one to remove that “.” Or you will get your phone in some sort of loop (I need to talk to the guys in Berlin about that)
P.S. Have I mentioned that Snom300 works just fine with Wave14?