XMPP on nagg.eu

XMPP audio and video calls

Sun, 03 May 2020 00:00:00 +0000

Ejabberd has supported STUN/TURN for quite some time now, this in conjunction with client support can be used to implement one on one audio and video calls.
Since version 2.8.0 Conversations Android client added audio and video call functionality by leveraging on STUN/TURN and XEP-0215.
The rest of the XMPP world is following the route opened by them, so I expect to see IOS and regular computer XMPP clients to finally implement these new features too in the upcoming months.
Enabling audio and video calls in Ejabberd is actually pretty simple.
Provided you have installed the latest release (version 20.04), edit ejabberd.yml:

Zabbix and XMPP alerts

Mon, 23 Oct 2017 17:44:14 +0000

Zabbix should theoretically be able out of the box to send alerts via XMPP.
For some reason this functionality does not work as intended, luckily it is possible to specify a custom script to send alerts; combining the aforementioned script with the Perl library sendxmpp is the easiest way to enable Zabbix from sending notifications via XMPP.

$ yum install sendxmpp

Create a bash script, this will be invoked by Zabbix to send notifications:

ejabberd XMPP server configuration guide

Mon, 11 Aug 2014 16:08:21 +0000

I will be keeping this post up to date to keep track on how to configure and mantain an ejabberd server working efficiently and secure. I strongly advise any reader to read carefully what is written here and not just copy-and-paste the configuration file.
My blog also contains a bunch of other posts regarding ejabberd that are worth giving a look at, use the search form.

Server


CentOS 7.5.1804 x86_64
Erlang/OTP 21.1.1-1 x86_64
ejabberd 18.09

Client


LineageOS 15.1 (Android Nougat)
Conversations 2.3.5+fcr

.:. Installation and initial configuration

Download and install erlang (release numbers here may not be up to date):

ejabberd and lost messages, possible “solutions”

Fri, 17 Jan 2014 14:30:12 +0000

Being the tinfoil hat I am I obviously don’t like nor use whatsapp, some time ago I set up my own XMPP server and made a bunch of close friends switch to it.
There are multiple clients for every platform, my personal preference goes to Xabber on Android and Pidgin on GNU/Linux; both support OTR encryption and all around are pretty decent clients.
The only real issue we had so far is the very annoying problem of lost messages; if the internet connection is stable and decent the problem will very likely never come up, too bad that mobile phone internet connection is everything but stable.
Every time there is a switch between EDGE, 3G, HSDPA and 4G the mobile phone is out of reach for some seconds (some time much more than just some).
The switch between let’s say 3G and HSDPA is not predictable, so the client has physically no time to notificate the server that he is about to close the connection and on the other hand the server also has some trouble knowing if someone suddenly disconnect.
Here comes XEP-199 a.k.a. XMPP ping, it is used to probe the clients connection state every X seconds, in my ejabbed (the XMPP server I use) configuration it is set to 60 seconds, so every 60 seconds the server ping every client, if after 32 additional seconds a client has not replied it will be considered as disconnected and any further message sent from everyone to it will be cached by the server and resent the next time the client will be back online.
Enable XEP-199 in ejabberd is pretty easy…