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how to manage airpods on linux

Tue, 07/21/2020 - 13:36

This article guides you on how to manage airpods and airpods pro on linux.

It uses pulseaudio and ofono telephony service for A2DP, HSP/HFP profiles.

Lets start…

1. Dependencies

sudo add-apt-repository ppa:smoser/bluetooth sudo apt-get install ofono-phonesim ofono git clone https://github.com/rilmodem/ofono.git /opt/ofono

2. Download the script

wget https://raw.githubusercontent.com/AkhilJalagam/pulseaudio-airpods/master/pulseaudio-airpods

3. Tweak the script for first time

replace MAC and card name in the script

AIRPODS_MAC='4C:6B:E8:80:46:84' # it should be somewhere in blueman-manager AIRPODS_NAME='bluez_card.4C_6B_E8_80_46_84' # you can find this using 'pactl list cards' command

4. Usage

pusleaudio-airpods connect/toggle_profile/disconnect


you should first pair your airpods using blueman-manager and trust them to use this script




The post how to manage airpods on linux appeared first on Lintel Technologies Blog.

Categories: Blog

Speed up SSH with multiplexing

Sat, 07/04/2020 - 13:52

SSH multiplexing is the ability to carry multiple SSH sessions over a single TCP connection.

OpenSSH can reuse an existing TCP connection for multiple concurrent SSH sessions. This results into reduction of the overhead of creating new TCP connections.

Advantage of using SSH multiplexing is that it speeds up certain operations that rely on or occur over SSH. For example, let’s say that you’re using SSH to regularly execute a command on a remote host. Without multiplexing, every time that command is executed your SSH client must establish a new TCP connection and a new SSH session with the remote host. With multiplexing, you can configure SSH to establish a single TCP connection that is kept alive for a specific period of time, and SSH sessions are established over that connection.

You can see the difference below

without multiplexing, we see the normal connection time:

$ time ssh lintel-blog

real 0m0.658s user 0m0.016s sys 0m0.008s

Then we do the same thing again, but with a multiplexed connection to see a faster result:

$ time ssh lintel-blog

real 0m0.029s user 0m0.004s sys 0m0.004s Configure Multiplexing

OpenSSH client supports multiplexing its outgoing connections, since version 3.9, using the ControlMaster, ControlPath and ControlPersist configuration directives which get defined in ssh_config. The client configuration file usually defaults to the location ~/.ssh/config.

ControlMaster determines whether ssh will listen for control connections and what to do about them. ControlPath sets the location for the control socket used by the multiplexed sessions. These can be either globally or locally in ssh_config or else specified at run time. Control sockets are removed automatically when the master connection has ended. ControlPersist can be used in conjunction with ControlMaster. If ControlPersist is set to ‘yes’, then it will leave the master connection open in the background to accept new connections until either killed explicitly or closed with -O or ends at a pre-defined timeout. If ControlPersist is set to a time, then it will leave the master connection open for the designated time or until the last multiplexed session is closed, whichever is longer.

Here is a sample excerpt from ssh_config applicable for starting a multiplexed session to server1.example.org via the shortcut server1.

Host server1 HostName server1.example.org ControlPath ~/.ssh/controlmasters/%r@%h:%p ControlMaster auto ControlPersist 10m


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Categories: Blog

How to install jitsi meet on CentOS 7

Tue, 05/12/2020 - 10:56

Jitsi is a set of Open Source projects that allows you to easily build and deploy secure videoconferencing solutions.

Jitsi Meet is a fully encrypted, 100% Open Source video conferencing solution that you can use all day, every day, for free — with no account needed.

1. Architecture

A Jitsi Meet installation can be broken down into the following components:

  • A web interface
  • An XMPP server
  • A conference focus component
  • A video router (could be more than one)
  • A SIP gateway for audio calls
  • A Broadcasting Infrastructure for recording or streaming a conference.

The diagram shows a typical deployment in a host running Docker. This project separates each of the components above into interlinked containers. To this end, several container images are provided.

2. Ports

The following external ports must be opened on a firewall:

  • 80/tcp for Web UI HTTP (really just to redirect, after uncommenting ENABLE_HTTP_REDIRECT=1 in .env)
  • 443/tcp for Web UI HTTPS
  • 4443/tcp for RTP media over TCP
  • 10000/udp for RTP media over UDP

Also 20000-20050/udp for jigasi, in case you choose to deploy that to facilitate SIP access.

E.g. on a CentOS server this would be done like this (without SIP access):

$ sudo firewall-cmd --permanent --add-port=80/tcp $ sudo firewall-cmd --permanent --add-port=443/tcp $ sudo firewall-cmd --permanent --add-port=4443/tcp $ sudo firewall-cmd --permanent --add-port=10000/udp $ sudo firewall-cmd --reload


3. Configuration

The configuration is performed via environment variables contained in a .env file. You can copy the provided env.example file as a reference.

a. Jibri Module Setup

Before running Jibri, you need to set up an ALSA loopback device on the host. This will not work on a non-Linux host.

For CentOS 7, the module is already compiled with the kernel, so just run:

# configure 5 capture/playback interfaces echo "options snd-aloop enable=1,1,1,1,1 index=0,1,2,3,4" > /etc/modprobe.d/alsa-loopback.conf # setup autoload the module echo "snd_aloop" > /etc/modules-load.d/snd_aloop.conf # load the module modprobe snd-aloop # check that the module is loaded lsmod | grep snd_aloop

b. Installation
  • clone the repository:

git clone https://github.com/jitsi/docker-jitsi-meet && cd docker-jitsi-meet

  • Create a .env file by copying and adjusting env.example
    • cp env.example .env
  • Set strong passwords in the security section options of .env file by running the following bash script
    • ./gen-passwords.sh
  • Create required CONFIG directories
    • mkdir -p ~/.jitsi-meet-cfg/{web/letsencrypt,transcripts,prosody/config,prosody/prosody-plugins-custom,jicofo,jvb,jigasi,jibri}
  • Run docker-compose up -d
  • Access the web UI at https://domain.com (or a different port, in case you edited the compose file).


If you want to use jigasi too, first configure your env file with SIP credentials and then run Docker Compose as follows: docker-compose -f docker-compose.yml -f jigasi.yml up

If you want to enable document sharing via Etherpad, configure it and run Docker Compose as follows: docker-compose -f docker-compose.yml -f etherpad.yml up

If you want to use jibri too, first configure a host as described in JItsi BRoadcasting Infrastructure configuration section and then run Docker Compose as follows: docker-compose -f docker-compose.yml -f jibri.yml up -d or to use jigasi too: docker-compose -f docker-compose.yml -f jigasi.yml -f jibri.yml up -d

Running behind NAT or on a LAN environment
If running in a LAN environment (as well as on the public Internet, via NAT) is a requirement, the DOCKER_HOST_ADDRESS should be set. This way, the Videobridge will advertise the IP address of the host running Docker instead of the internal IP address that Docker assigned it, thus making ICE succeed. If your users are coming in over the Internet (and not over LAN), this will likely be your public IP address. If this is not set up correctly, calls will crash when more than two users join a meeting.

The public IP address is discovered via STUN. STUN servers can be specified with the JVB_STUN_SERVERS option.


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Categories: Blog