Josh’s FreeSWITCH Notes

Configuration directories

How do I get the configuration directories from FreeSWITCH again? Nick vs Networking shows a command for getting all _dir paths:

$ fs_cli -x "global_getvar" | grep _dir
base_dir=/nix/store/xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx-freeswitch-1.xx.x
recordings_dir=/var/lib/freeswitch/recordings
sounds_dir=/etc/freeswitch/sounds
conf_dir=/etc/freeswitch
log_dir=/var/log/freeswitch
run_dir=/run/freeswitch
db_dir=/var/cache/freeswitch
mod_dir=/nix/store/xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx-freeswitch-1.xx.x/lib/freeswitch/mod
htdocs_dir=/nix/store/xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx-freeswitch-1.xx.x/share/freeswitch/htdocs
script_dir=/nix/store/xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx-freeswitch-1.xx.x/share/freeswitch/scripts
temp_dir=/tmp
grammar_dir=/nix/store/xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx-freeswitch-1.xx.x/share/freeswitch/grammar
fonts_dir=/nix/store/xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx-freeswitch-1.xx.x/share/freeswitch/fonts
images_dir=/nix/store/xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx-freeswitch-1.xx.x/var/lib/freeswitch/images
certs_dir=/nix/store/xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx-freeswitch-1.xx.x/etc/freeswitch/tls
storage_dir=/var/lib/freeswitch/storage
cache_dir=/var/cache/freeswitch
data_dir=/nix/store/xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx-freeswitch-1.xx.x/share/freeswitch
localstate_dir=/nix/store/xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx-freeswitch-1.xx.x/var/lib/freeswitch
    

And now I’m trying to remember how I actually set the script_dir to be something else.

Ah, it’s by providing a “-scripts” argument when launching FreeSWITCH. So I need to modify my systemd service that adds that.

Users

For logging into SIP, user configuration is located in directory/default/.

ACLs

Allowed IP addresses are listed in autoload_configs/acl.conf.xml, which is used by <param name="apply-candidate-acl" value="XXXXXX"/> in sip_profiles/internal.xml.

fs_cli configuration

If you modify the password for fs_cli (which you probably should), you’ll probably want to configure the password so you don’t have to type it as a command argument. You’d put the following in ~/.fs_cli_conf:

[default]
; Put me in ~/.fs_cli_conf
password => some_secret_password

Call bridging

Note to self: Need to get call ringing to a softphone to actually play a ringing tone. Supposedly, setting <action application="set" data="ringback=${us-ring}"/> should work, but it hasn’t so far. Maybe I need to check if ${us-ring} exists? Oh, eval $${us-ring} returns %(2000,4000,440,480).

While testing bridging with Gnome Calls, I noticed that bridging immediately failed while origination succeeded. Looking at debugging output of gnome calls I see:

20:26:09.9716       CallsSipOrigin[1077203]: WARNING: No common codecs in SDP. Hanging up. Remote SDP:
v=0
o=FreeSWITCH 1772148003 1772148004 IN IP4 ░░░░░░░░░░░
s=FreeSWITCH
c=IN IP4 ░░░░░░░░░░░
t=0 0
m=audio 18366 RTP/AVP 9 101 13
a=rtpmap:9 G722/8000
a=rtpmap:101 telephone-event/8000
a=fmtp:101 0-15
a=rtpmap:13 CN/8000
a=ptime:20

but when testing with origination I see:

20:28:21.3234       CallsSipOrigin[1077203]:   DEBUG: Remote SDP was set to:
v=0
o=FreeSWITCH 1772148603 1772148604 IN IP4 ░░░░░░░░░░░
s=FreeSWITCH
c=IN IP4 ░░░░░░░░░░░
t=0 0
m=audio 17898 RTP/AVP 102 9 0 8 104 105 101 13
a=rtpmap:102 opus/48000/2
a=fmtp:102 useinbandfec=1; maxaveragebitrate=30000; maxplaybackrate=48000; ptime=20; minptime=10; maxptime=40
a=rtpmap:9 G722/8000
a=rtpmap:0 PCMU/8000
a=rtpmap:8 PCMA/8000
a=rtpmap:104 telephone-event/48000
a=fmtp:104 0-15
a=rtpmap:105 CN/48000
a=rtpmap:101 telephone-event/8000
a=fmtp:101 0-15
a=rtpmap:13 CN/8000
a=ptime:20
m=video 19584 RTP/AVP 103
b=AS:1024
a=rtpmap:103 VP8/90000
a=rtcp-fb:103 ccm fir
a=rtcp-fb:103 ccm tmmbr
a=rtcp-fb:103 nack
a=rtcp-fb:103 nack pli

I was wondering which codecs Gnome Calls maybe uses, so here’s its local SDP (I guess PCMU/PCMA):

v=0
c=IN IP4 ░░░░░░░░░░░░
m=audio 40907 RTP/AVP 0 8
a=rtpmap:0 PCMU/8000
a=rtpmap:8 PCMA/8000
a=rtcp:37621

Asking an LLM and looking at FreeSWITCH codec negotiation explained docs, I first tried setting the variable codec_string (but that didn’t work) and eventually arrived at:

	<action application="export" data="nolocal:absolute_codec_string=PCMA,PCMU"/>
	<action application="bridge" data="{bridge_early_media=true,ignore_early_media=true}user/1000"/>

which did work. However, it didn’t get ringing to the softphone. I should have known softphones don’t really have early media. What seemed to work was removing bridge_early_media and adding instant_ringback=true.

	<action application="set" data="instant_ringback=true"/>
	<action application="bridge" data="{ignore_early_media=true}user/1000"/>