Port 5060 & 5090 issues with BT Smarthub 2

[Kryten]

I recently setup a 3CX lab using Windows after attending the online basic course led by Nicholas Paras.
Nicholas REALLY explains thing very well and I am "reasonably sure" that the issue is with the router but it left me a little puzzled!

1. This is a strange one - everything WORKS on my 3CX lab but the port test for 5060 & 5090 fails!

2. The route is a BT SmartHub 2 and the ports, 5060 & 5090, have been configured to forward correctly and ALG disabled.

3. I can only assume that BT are doing something with these ports on the router, as it already has a disabled anaologue voice port installed, but I am puzzled why it still works externally.

4. Port setup issues "seem" likely to be a common problem on new installs or possibly if the customer changes their broadband.

5. Other than resolving it with the hardware and/or the carrier - I have even allocated 6060 & 6090 instead with exactly the same results. And even with NO port forwarding at all for these 2 ports it works.

I am probably over looking something really basic but I cannot see it. It would be really nice to figure this one out just in case I have a similar issue on a customer site.

Kind regards

John


(cut down version of the results)

resolving 'stun-eu.3cx.com'... done
resolving 'stun2.3cx.com'... done
resolving 'stun3.3cx.com'... done
resolving 'sip-alg-detector.3cx.com'... done
testing 3CX PhoneSystem 01 SIP Server... failed (How to resolve?)
stopping service... done
detecting SIP ALG... not detected
testing port 5060... Mapping does not match 5060. Mapping is 20005. (How to resolve?)
starting service... done
testing 3CX PhoneSystem Media Server... failed (How to resolve?)
stopping service... done
testing port 5090... Mapping does not match 5090. Mapping is 20006. (How to resolve?)
testing ports [9000..9398]... done
testing port 9000... done
testing port 9002... done
testing port 9004... done
etc.

 

[plkr-webmaster]

Following this as I have the exact same issue.

Everything works well, but 5060 and 5090 still fails.

Don't suppose you figured it out?

 

[Kryten]

No yet!
Which type of DSL device are you using?

I also tried modifying the port numbers, to 6060 & 6090 on a new installation of 3CX but it pretty much does the same thing!

Wire shark shows it using different ports at the other end so I suspect either my router or carrier are doing something, probably to keep them free for their use, to these ports.

 

[JohnS_3CX]

If your provider does not honor the port forwards (as evident above) then consider switching to a hosted solution, and installing a 3CX SBC locally to bypass these issues entirely.

If you go with a 3CX-hosted machine then all your ports will be preconfigured and accessible, and the 3CX SBC you will install locally will help "bridge" up your phones to 3CX. It won't really mind what your ISP is doing portwise because it uses random outbound ports anyway.

https://www.3cx.com/ordering/pricing/hosted-info/

 

[Kryten]

Thank you for the info.
Sorry it has taken a while to get back to you but it has been a very busy week.

1. We are still evaluating the 3CX and are currently looking at the locally installed machines on temporary work sites.

2. Sometimes these sites "lose" their internet connections for a variety of reasons such as the cable/fibre being dug up or drove through on site and just for fun the wireless backup does not kick in!

3. Would the the 3CX-hosted machine lost connections between the different extensions if the network were lost?
I have read the article https://www.3cx.com/ordering/pricing/hosted-info/
and it would appear that they would lose this function in the case of a network failure?

4. Or would it be better to use a local Windows 10 machine so that local extensions would be maintained?

5. With a local machine we could still, in some cases, take advantage of local analogue lines by using an ATA? This is particularly useful on some of a harder to access sites.

5. I am still trying to figure out WHY the 3CX still appears to be FULLY functioning, even though the provider does not honour the port forwards, AND it fails the port test, does this REALLY have any impact on the practical working of this product?

 

[JohnS_3CX]

1. We are still evaluating the 3CX and are currently looking at the locally installed machines on temporary work sites.

Understood.

2. Sometimes these sites "lose" their internet connections for a variety of reasons such as the cable/fibre being dug up or drove through on site and just for fun the wireless backup does not kick in!

If the machine is in the cloud, mobile apps will continue to work over 4G/LTE at least, and can make internal/external calls.

If the machine is local, you will only be able to make internal calls to each other.

3. Would the the 3CX-hosted machine lost connections between the different extensions if the network were lost?
I have read the article https://www.3cx.com/ordering/pricing/hosted-info/
and it would appear that they would lose this function in the case of a network failure?

Yes it would, but as above, if you make use of the mobile apps (along with deskphones) you will continue to have internal/external calls over 4G/LTE. This will work even if the site loses both internet and power.

4. Or would it be better to use a local Windows 10 machine so that local extensions would be maintained?

You could, but as above it will still have its downsides (ie. you lose the benefits the apps provide when you are cloud based)

5. With a local machine we could still, in some cases, take advantage of local analogue lines by using an ATA? This is particularly useful on some of a harder to access sites.

Sure, but if you are worried about stuff being dug up, analog lines will also suffer the same fate no? Also think long term, the analogue switch off will be in a 3 years if I remember correctly. You will need to redo your stuff anyway at that point, so might as well make the decisions today.

5. I am still trying to figure out WHY the 3CX still appears to be FULLY functioning, even though the provider does not honour the port forwards, AND it fails the port test, does this REALLY have any impact on the practical working of this product?

The thing with ports being remapped/rewritten is that it works until it doesn't. It's a roll of the dice basically, and you depend on the ISP hardware being smart enough to not mess things up. But the rudimentary logic built into ISP hardware which governs SIP is not bullet-proof, we often see cases where it works fine to a point, and then you either have one way audio or lose audio completely at the worst time possible. Put simply, it's unreliable / unpredictable because you are not in full control. Hence the 3CX SBC, which was made to work in such environments to tunnel its way up to the cloud.

Ultimately I think having your machine in the cloud (whether self-hosted or 3CX-hosted) is going to be a superior solution if you include the apps in your communications. If you don't plan on using any apps then you can host it locally but when internet access goes down, so do the trunks / external lines.

 

[digitaldatatechs]

In order for the firewall test topass, you have to disable source port remapping in your router NAT policies.

 

[digitaldatatechs]

Also make sure SIP{ alg is disabled.

 

[digitaldatatechs]

SIP ALG

 

[Kryten]

Thank you for the information.

ALG is not a problem - ' detecting SIP ALG... not detected'
and unfortunately there does not appear to be a user option with the BT Smarthub 2 to disable source port remapping.

3CX tech support are very much aware of these problems and have been very helpful - see above comments from 3CX support team for more details.

 

[digitaldatatechs]

I had similar issues when I began using 3cx. Honestly, I use the Debian distro as a vm and it's very stable. I do self host and plan to continue to self host. Cloud hosting is another expense and if you have a virtual platform already, it makes it much easier to manage all of it and gives you the control, not someone else you purchased hostiung from.
If I can be any help, let me know.

 

[Kryten]

Thanks for the advice and offer of help - perhaps you could clarify if I have understood the 3CX SBC soloution correctly?

The chances of finding an existing broadband service on a site that does not use source port remapping can be, in my opinion, quite low and to get them sorted out in the 'time scales required' is not always practical.

1. Does the 3CX SBC option only works in conjunction with cloud based 3CX?
2. 3CX SBC software can be installed on a local hardware platform such as a PC running W10?
3. So would the LOCAL extensions still be able to call each other if, in the worst case, there is a break in the outside network?
4. Could a local ATA be used as an emergency line with the SBC in place?

That's it!

 

[cobaltit]

1. 3CX SBC does not know or care about where or how 3CX is hosted.
2. 3CX works fine on a W10 machine. System requirements are listed here: https://www.3cx.com/docs/recommended-hardware-specifications-for-3cx/
3. 3CX SBC does not provide local survivability
4. ATA needs to be local to 3CX.

 

[atlan1]

Hi all, Think I can add some info here regarding the BTB Smart hub 2. for a start there is nothing smart about them, lets get that out of the way.

Having had a very lengthy call with BT Technical It was revealed that Smarthub2's do not allow 5060 or 5090 to be pinholed this is because Smarthub2's use these ports to take updates for the hubs firmware. Not a very smart move on BT's part because it renders them useless for use with any SiP PBX or SiP Trunk provider that requires them. Hope this gives you some insight as to why they are not very smart.

My advice get a Draytek 28xx series they work flawless with 3CX and any other self-hosted service you care to use with them.

Stay safe