3CX SBC

[jpskinner]

Deploying two SBC servers at a hospital who have strict firewalls in place, and I would like to know exactly how the SBC works and how the phones show on the "Phones" page of 3CX.

I have a VLAN 46 which has been setup, however I know that the SBC and phones need to be on the same VLAN; however, I need to know if the Yealink phones support Option 66 DHCP so that it will automatically grab the provisioning file, and furthermore I need to know if the phones support LLDP.

E.G. I plug in a Yealink phone anywhere in the hospital and it automatically grabs the VLAN and can be discovered by the SBC, allowing me to assign it to a user.

Would option 66 be a good idea?
How has everyone else set this up?
Any ideas please?

Thanks!!

 

[Saqqara]

Phones.

In order to provision the phones, you need outbound https port open (443 or 5001), as this is used by the phones.
NTP access will also be required, unless you configure an internal time server

Phones do support dhcp option 66 - https://www.3cx.com/sip-phones/dhcp-option-66/

If the phone gets an ip address on the same network as the SBC, they should appear in the management console where you can assign them to the required extension.

LLDP you configure on the switch, and not the phone itself.

SBC Server

The sbc servers need 3cx tunnel port outbound (tcp / udp port 5090),

http / https / ntp maybe required for normal running i.e. updates, time

 

[ChrisC_3CX]

Just to clarify what Saqqara said regarding the SBC, in addition to the tunnel port, the 3CX SBC requires outbound traffic to be allowed to the PBX's TCP port 5001 (if not 5001 then your set HTTPS port).

For the IP Phones to come up in the 3CX Phones section, the multicast traffic they send on IP 224.0.1.75 must be able to reach the 3CX SBC. This is why we recommend that both the SBC and the IP Phones are on the same subnet.

What I would recommend is, before setting up Option 66 on your DHCP, you actually do a first time provisioning of all phones via 3CX's PnP so that you get them assigned to extensions and also get them provisioned at the same time. Then, you can set up option 66 to enable IP Phones to reprovision even if they get reset.

 

[jpskinner]

Just to clarify what Saqqara said regarding the SBC, in addition to the tunnel port, the 3CX SBC requires outbound traffic to be allowed to the PBX's TCP port 5001 (if not 5001 then your set HTTPS port).

For the IP Phones to come up in the 3CX Phones section, the multicast traffic they send on IP 224.0.1.75 must be able to reach the 3CX SBC. This is why we recommend that both the SBC and the IP Phones are on the same subnet.

What I would recommend is, before setting up Option 66 on your DHCP, you actually do a first time provisioning of all phones via 3CX's PnP so that you get them assigned to extensions and also get them provisioned at the same time. Then, you can set up option 66 to enable IP Phones to reprovision even if they get reset.

I see, thank you that helps a lot!

So, with option 66, can that be used with the SBC deployment. Instead of manually clicking each phone and pressing assign extension, can I just add the MAC address to the extensions profile and let option 66 provision the phone?

I am also adding option 132 to add the VLAN tag to all Yealink phones as I did a bit of research last night - hoping that will not affect anything on the 3CX side.

Once we have deployed over 500 phones, I will be moving the PBX on-site to handle the rest - I am guessing I can easily change the option 66 provisioning string to local LAN to avoid the hassle of re-configuring all of the phones?

 

[Saqqara]

You may want to rethink the number of SBC servers - https://www.3cx.com/docs/recommended-hardware-specifications-for-3cx/

 

[jpskinner]

You may want to rethink the number of SBC servers - https://www.3cx.com/docs/recommended-hardware-specifications-for-3cx/

Yes, I am aware thank you. I am using cluster mode, so have 2 servers for 100 extensions then will expand on that with new SBCs

 

[ChrisC_3CX]

So, with option 66, can that be used with the SBC deployment. Instead of manually clicking each phone and pressing assign extension, can I just add the MAC address to the extensions profile and let option 66 provision the phone?

Yes but as you said, you would have to add the device model and MAC address to the extension manually in the Management Console. Using 3CX's PnP feature to do this should be easier to add them in my opinion.

Once we have deployed over 500 phones, I will be moving the PBX on-site to handle the rest - I am guessing I can easily change the option 66 provisioning string to local LAN to avoid the hassle of re-configuring all of the phones?

You can but you would also have to:

1. Change the provisioning method of the IP Phones in the "Management Console >> Extensions >> Edit >> Phone Provisioning", from SBC to Local Lan.
2. Factory reset all devices after the migration is complete for them to deprovision as Local Lan devices. Factory resetting them is required to get rid of remnant SBC settings that would not be cleared otherwise.

 

[Saqqara]

If you add the phone to 3CX management console first using dhcp will automatically configure the phone.

If you move the 3CX server internally , you will have to change the provisioning method of all the phones to local lan and not sbc.

 

[jpskinner]

Yes but as you said, you would have to add the device model and MAC address to the extension manually in the Management Console. Using 3CX's PnP feature to do this should be easier to add them in my opinion.


You can but you would also have to:

1. Change the provisioning method of the IP Phones in the "Management Console >> Extensions >> Edit >> Phone Provisioning", from SBC to Local Lan.
2. Factory reset all devices after the migration is complete for them to deprovision as Local Lan devices. Factory resetting them is required to get rid of remnant SBC settings that would not be cleared otherwise.

Thanks! I understand what you mean, however from a roll-out perspective it would be easier to do all the programming on the management console then drop ship the devices to site and they can just plug them in and it'll all be provisioned using option 66.

Got ya! Anyway I can send out a mass factory reset command, such as via a phone template or something?

 

[ChrisC_3CX]

Anyway I can send out a mass factory reset command, such as via a phone template or something?

Can't be done via 3CX I'm afraid, but you could possibly check the vendor's documentation and see if there's a way to force the device to reset via other methods apart from its UI and buttons. Depending on what those methods are you might be able to use them to trigger a mass factory reset of the devices.