Raspberry Pi SBC Tips and Tricks

[Alphabetic]

Hi Guys,

I've started my journey down the SBC route using a Raspberry Pi 3.

I've gone through the installer and i'm apparently set up ready to go.

I have tried provisioning any phones yet as I just wanted to check from both ends that they're up and connected.

I'm looking for any tips or useful info people have to viewing their SBC status?

From the Pi i've done netstat | grep 5090 Which shows TCP/UDP established to the WAN IP of 3CX.

Is there a way I could see from 3CX that whows the SBC has connected and is connected?

Theres a lot of logs, i'm not sure which I need to look at.

thanks!

 

[Justin D]

I've not found anyway of knowing if the SBC has connected from the console, and I believe there may be a feature request being worked on to add one.

I installed one this week and did a factory reset on the phones and they provisioned a treat, so far its worked well with no issues - just go for it!

 

[eddv123]

There is a feature request that has been pending for sometime now - it would be good to know when this will be available: https://www.3cx.com/community/threads/3cx-sbc-status-in-admin-gui.42985/

The two ways I currently use:

* Look at the 3CX Tunnel log in the supportinfo file - even if you are new to 3CX it should not be overally difficult to understand what is going on here.

* Plug in a phone into the remote site - if it appears in the "phones" list with :SBC next to it (and the correct mac code obviously) your tunnel is up.

 

[Alphabetic]

Right, Just factory reset my Fanvil and saw it in the phones tab. Assigned it to EXT and viola. Nice and simple that.. no messing around on customer firewall changing ports and stuff. I am pretty impressed with that.

Do I not need to bother with PBX delivers audio for SBC phones?

What is a decent size GB for the SD card? For logging and such?

 

[eddv123]

No you don't - the SBC does not require "PBX Delivers audio" as all the traffic is kept locally on the remote site (which will help you save bandwidth).

That setting is only used when configuring phones with the remote STUN method.

I use a Pi with a 16GB card and don't have any issues, but you can go for more if you want.

 

[Alphabetic]

Excellent.

Just configured another 2 phones in minutes without having to prat around on the firewall. Saves time and £££.

Do you know if it's possible to swap SD cards between the same Pi HW and be up and running or do you have to set up static IP again?

 

[leejor]

Do I not need to bother with PBX delivers audio for SBC phones?

What is a decent size GB for the SD card? For logging and such?

PBX Delivers audio is usually only required to "get around" audio issues, when using multiple sets at one location, and STUN. Using the SBC means you don't require that.

I'm not certain how much logging actually happens on the card, if any. SD cards are now so inexpensive that I find it's not worth buying anything smaller than a 16Gb.

 

[leejor]

Do you know if it's possible to swap SD cards between the same Pi HW and be up and running or do you have to set up static IP again?

Unlike the 3Cx server, the MAC of the Pi is not "critical", so you should be able to swap (or clone), the SD card as needed.

 

[eddv123]

The SD card and hardware are separate (the SD card will take all the configuration) so if you were to swap SD cards it would require new IP configuration.

 

[leejor]

If you removed the current card, put it into an adapter, insert that, along with a second "new" SD card into a PC, you should be able to copy all of the files over to the a new (larger?) card, the put that one back into the Pi, and you should be up again.

 

[Marari]

@leejor @kieferschild

Or you can build this:

https://www.3cx.com/community/threads/raspberry-pi-sbc-resilience.59706/#post-251074

 

[Alphabetic]

Can someone tell me how the IP phones on the LAN locate the local SBC? Just wondered how that works.

 

[Saqqara]

When you factory default the phone, SBC will pick up the PNP and route it to the 3CX server

 

[cobaltit]

This is a basic outline on how SIP PnP works. It's focused on the 3CX server but the SBC operates in a similar fashion:

https://www.3cx.com/docs/plug-and-play-ip-phone/

 

[Wendelspanswick]

Just to add we have tried installing a Pi on an NHS network that uses an N3 connection to the WAN and we have hit all sorts of issues, mainly that the SBC is unable to tunnel out.
We have a meeting with the NHS IT department to try and find a workaround.

 

[Wendelspanswick]

If you get any issues and want to look at the logs on the Raspberry Pi SBC here is my crib sheet:

SBC Logging
Open Terminal Window
1) sudo nano/etc/3cxsbc.conf
2) Change NONE to DEBUG
3) Save and Exit
4) Stop the 3cxsbc service (service 3cxsbc stop)
5) Stop the rsyslog service (service rsyslog stop)
6) Delete file ls -l /var/log/ (rm /var/log/3cxsbc.log)
7) Recreate /var/log/3cxsbc.log (touch /var/log/3cxsbc.log)
8) Start the rsyslog service (service rsyslog start)
9) Start the 3cxsbc service (service 3cxsbc start
Use the file manager to browse to /var/log/3cxsbc.log and open with text editor or Libre etc.
Remember to change 3cxsbc.conf back to NONE

 

[Saqqara]

Just to add we have tried installing a Pi on an NHS network that uses an N3 connection to the WAN and we have hit all sorts of issues, mainly that the SBC is unable to tunnel out.
We have a meeting with the NHS IT department to try and find a workaround.

Being a corporate network, you will probably find the firewall is locked down - you need tcp/udp port 5090 and tcp 5001 outbound.

 

[Alphabetic]

Tip:

Modifying the SBC Name within the 3CXSBC.conf file to something more identifiable makes it easier to find it the 3CX Tunnel logs