BLF for PSTN how to make?


I’ve got 4 pstn lines in office and need connect it to asterisk with Yealink SIP-T26P connected. BLF buttons of SIP-T26P should show status of every pstn line.

I’ve searched forum and googled and found different answers. Someone write that it does not work totally, someone write that it works only with external FXO gates. But I preffer internal cards, like

Can you say, what solution will guaranteed work?
Many thanks in advance.

You need hints. Beyond that it should work. Can you provide your dialplan and the result of core show hints?

I’ve just started with Asterisk. And my simplest dialplan contains only two SIP clients for two connected SIP-T26P.
I need purchase hardware to connect pstn line for further testing. But I don’t know WHAT harware I should buy for BLF with pstn will guaranteed work.

I have to leave this to the circuit switched experts, but I think the answer is going to depend on what features you are prepared to sacrifice. I suspect that you will have to lose the ability to automatically hunt for a free line.

It’s not really going to depend on exact models, rather more the general inteface, so I would suggest that a simple, analogue, interface, like the TDM4 series will work, if anything will work. The dialplan needs to be able to address it at the circuit level, rather than the group level.

I do not believe that the dialed digits will ever be considered in determining the state of hints.

You should be carefully asking yourself whether you are trying to emulate a legacy system when there may be a better way of doing things. The BLF on a switch and lamp unit may be more to do with putting the free line search onto the user than anything of benefit to the user.

As far as I know lines may be united into one group and dialplan may address outgoing rings to this group. No matter it’s PSTN lines or SIP trunk to FXO gate.

It’s not for ordinary user. Only for receptionist and manager. They should have this fumctionality by design specification (not mine).

Apart from DAHDI /g syntax, Asterisk has no concept of trunk groups. That is particularly true of SIP, where there are cases where it would be useful to treat a trunk differently from an extension. Of course, there are no identifiable lines within a SIP trunk, so you couldn’t use hints on them, only on the overall trunk.

Many Asterisk GUIs simulate a trunk concept, but at the dialplan level.

To do BLF on a DAHDI device that uses /g syntax, you would also need to be able to use the / syntax for the component lines. I don’t know if you can do that, and, in the case of common channel signalling, I’m not sure if you can even use the / syntax, which is why you need an answer from someone with circuit switched network experience.

Using simple FXO cards means that trunks have to be created in the dialplan, so there should be no difficulty getting hints for individual device channels.

Specifications often reflect the historic system or the specifier’s experience, rather than the best use of current technology.

Using simple FXO cards means that trunks have to be created in the dialplan, so there should be no difficulty getting hints for individual device channels.[/quote]

Actually, it is possible that g works in this case as well, but it still remains possible to address the individual lines and I would hope that hints would work at that level, even if calls were set up at the group level.

Sorry for reply to a old post but when i search on google this post is the only whit sense.
I’m on Elastix 2.4.0

FXO with DAHDI card PCI/E
I edit extensions_custom.conf

exten => line1,hint,DAHDI/1
exten => line1,1,Dial(DAHDI/1) 

where 1 is my FXO port

And on my Phone , I add BFL -> line1
Work like a charm, out or inn

This is my little contribution :smiley: