SBC Up and Down 74 Times Today

[JurisTekton]

We are a small outfit with 7 users on the 3CX Free program with a Telxi trunk. We don't have a dedicated IT Manager but I am moderately IT-competent and managed to install and set-up our hosted system and we have 4 x YealinkT54W s and 3 Yealink T58As in use and a few of each in reserve for additional users if we ever have any. I did not fully understand the requirement for a SBC when I se-up our system but, because we auto-provision our phones, one of the T54Ws was set up as a router phone and acts as SBC. If I had known more about it at the time, I would have set up my phone, a T58A, as the router phone but it was set up automatically on an ordinary users phone which is not ideal as I have be sure they don't accidentally unplug the power or the network cable (its wired to a wall socket with a switch at the other end which in turn is connected a DrayTek 2927Lax-5G security router (5G because although our building is in central London, there is no fibre connection available and VDSL only gives us 40Mb/s whereas the 5G system gives us on average about 600Mb/s, more late at night). It seemed to be quite a complicated performance to move the SBC once it has been set up and the other phones provisioned to use the router phone's static private IP address as outbound proxy so \I have left it. We have tried to use some stand-along VOIP phones and a Yeastar MyPBX in the past which we could not get to work reliably because of the CG-NAT our 5G provider use with a dynamic public IP address. We tried devices like an Ingate SIParator set up in SBC mode and it didn't help much and we were losing about 1 in 3 calls. The 3CX system with the router phone SBC has worked perfectly for 9 months and counting.. Anyway, you get an idea of our infrastructure. Most days there is a message in the Event Log that says "Trunk SBC 'Yealink T54W (20xxx)' (148.252.xxx.xx/192.168.0.64) has changed status to Down/Up". The 148 IP address is the dynamic public IP address behind CG-NAT (it is not the static IP address oft the SBC tunnel - should it be?). The 198 IP address is obviously the private static IP address of the router phone. When we got these messages - one up, one down - once a day on most days we weren't too concerned as the gap between the up and down message is less than a minute usually. Today, however, we had had the message 76 times, half down, half up and this is now a concern. Out internet service is usually very stable but today it has dropped out quite a few times, which we blame our ISP for because there was nothing obviously wrong with the router or phone setting and nothing had changed since yesterday when we didn't have any problems. What is likely to be causing the SBC to go down and back up so many times? Is it a big problem? Is there something I need to change in the settings in 3CX, the router, the router phone or the other phones?. I don't want 3CX becoming concerned about the frequent up and down status of the SBC. Calls have worked fine all day but I am worried there might be something seriously wrong with our set-up/configuration that might affect the 3CX system. If there are things we should check, please explain without too much jargon. i am IT-competent but not an It-professional. We have had the 3CX system for about 9 months so I am reasonably familiar with it but my actual job is not IT related so I can get a bit lost with the more complicated stuff. If you have read this far, I thank you. If you have any advice for me, I thank you again in advance.,

 

[fxbastler]

The basic question: Are there any noticeable problems with the phones or calls other than the messages in the 3CX?

What is likely to be causing the SBC to go down and back up so many times? Is it a big problem? Is there something I need to change in the settings in 3CX, the router, the router phone or the other phones?

our experience:

Combining 5G (CG-NAT only) with a single router phone as an SBC for other phones could be problematic.

It's probably better to use a single, more reliable (separate) 3CX SBC for all phones, or, if possible, connect all phones (there are only a few) individually to 3CX as router phones.

If technically possible, I would use the VDSL internet connection exclusively for telephony - even if it's slower. In our experience, this is more stable and more important for telephony. But that's just my opinion.

 

[JurisTekton]

The basic question: Are there any noticeable problems with the phones or calls other than the messages in the 3CX?



our experience:

Combining 5G (CG-NAT only) with a single router phone as an SBC for other phones could be problematic.

It's probably better to use a single, more reliable (separate) 3CX SBC for all phones, or, if possible, connect all phones (there are only a few) individually to 3CX as router phones.

If technically possible, I would use the VDSL internet connection exclusively for telephony - even if it's slower. In our experience, this is more stable and more important for telephony. But that's just my opinion.

Thanks for your reply and the answer to your question is no, it has not affected the use or functioning of the phones and we had incoming and outgoing calls as usual on Friday. I like the idea of an external SBC more than a separate VDSL network for the phones. Do 3CX still provide the software to set up a SBC on a Raspberry Pi? I could probably manage to do that and it might be easier or we have some spare mini PCs and I could use one of them as a dedicated SBC.

 

[fxbastler]

Do 3CX still provide the software to set up a SBC on a Raspberry Pi?

https://www.3cx.com/docs/installing-pbx-raspberry-pi/

 

[SteveITS]

@JurisTekton Repeated reconnections are likely small amounts of packet loss.

 

[paulodagraca]

Hello,

If you are able to setup a raspberry pi as a SBC, then Yes go for it.
But not sure this will help with the SBC connection droppings and logs/per day, as i think this is related to the ISP connection.
And as for the logs... if it does not impact the calls let it be, just ignore.

Paulo