Thursday, October 30, 2008

Understanding ShoreTel Phones Boot up Process

So I was answering a friend who had inquired about how the boot up process works on a ShoreTel phone when I thought....hummmm...this would make a great blog entry because I'll forget iit n a few months. :)
So assuming we have the network configured as I have shown in the last blog entry (VOIP vlan 19, user vlan 14), we plug a brand spanking new phone into the switch on port A1.  Assuming you have your DHCP server set up correctly (which we will cover in just a minute) the phone will be into the untagged vlan 14 and request a DHCP address.  It gets one, but it also get the DHCP Option 156.  This option is used by the ShoreTel phone to determine where it's vmail server is as well as where it should live in the network. It see's that it should live in vlan 19 and reboots.  Now it uses tagged info on vlan 19 to request a new  DHCP address.  This time it gets one in the 10.3.9.x range and goes about its business.  One thing I fail to mention here is the first time this happens it's reboot city for the phone.  New phones, even out of the box seem to need an upgrade when the connect to the ShoreTel server.  On my gig network this first boot and config of the phone takes like 10 minutes.
Ok, on the DHCP server we have to set up option 156.  First right click on the DHCP server in the DHCP Server Manager tool and select "Set pre-defined options".  Here you need to add option 156 so it appears as an option at the vlan scope level. Set the data type to string.  Once the item is created go to vlan 14 (which the phone first boots looking for the info) and add scope option 156.    The string format should be something like:
ftpservers=, country=1, language=1, layer2tagging=1, vlanid=19 is the address of the ShoreTel server, country is set to USA, language is set to english, layer2tagging is set to 1 or yes and vlanid is the vlan id of the vlan for voip.
Cool stuff.


JaguaR said...

Hi there,
Great post, but I have some missunderstandings here. I have a HP ProCurve 26xx switch 2 SG90 ShoreTel switches and 1 SBS server. I configured 10 ports untagged VLAN1 (for future use also), 10 ports tagged VLAN2, and configured DHCP scope with option 156 on SBS server. Now I have to plug the SBS NIC into untagged ports or? My setup is correct?
Thank you.

Rolfsa said...

Not a whole lot of info to go on there...but the server goes into an untagged port. Your phone should be untagged on the user vlan (where option 156 is set) and tagged on the phone vlan. Without understanding more of your config I can't validate your config.

Rob said...

There are companies that do this kinds of stuff for you. My neighbor works for ZAG Technical, and they can do network validation for Shoretel systems. If you are going to do it, why not do it right.

Anonymous said...

The 156 string looks incorrect. Should be "vlanid" not "vlandid".

Rolfsa said...


Anonymous said...

does it get the vmail address or the HQ address as they can be configured differently?