The following sections describe how to install coturn (which implements the TURN REST API).
The TURN daemon
coturn is available from a variety of sources such as native package managers, or installation from source.
Just install the debian package:
sudo apt install coturn
This will install and start a systemd service called
Download the latest release from github. Unpack it and
cdinto the directory.
You may need to install
libevent2: if so, you should do so in the way recommended by your operating system. You can ignore warnings about lack of database support: a database is unnecessary for this purpose.
Build and install it:
make sudo make install
Create or edit the config file in
/etc/turnserver.conf. The relevant lines, with example values, are:
use-auth-secret static-auth-secret=[your secret key here] realm=turn.myserver.org
turnserver.conffor explanations of the options. One way to generate the
pwgen -s 64 1
realmmust be specified, but its value is somewhat arbitrary. (It is sent to clients as part of the authentication flow.) It is conventional to set it to be your server name.
You will most likely want to configure
coturnto write logs somewhere. The easiest way is normally to send them to the syslog:
(in which case, the logs will be available via
journalctl -u coturnon a systemd system). Alternatively,
coturncan be configured to write to a logfile - check the example config file supplied with
Consider your security settings. TURN lets users request a relay which will connect to arbitrary IP addresses and ports. The following configuration is suggested as a minimum starting point:
# VoIP traffic is all UDP. There is no reason to let users connect to arbitrary TCP endpoints via the relay. no-tcp-relay # don't let the relay ever try to connect to private IP address ranges within your network (if any) # given the turn server is likely behind your firewall, remember to include any privileged public IPs too. denied-peer-ip=10.0.0.0-10.255.255.255 denied-peer-ip=192.168.0.0-192.168.255.255 denied-peer-ip=172.16.0.0-172.31.255.255 # recommended additional local peers to block, to mitigate external access to internal services. # https://www.rtcsec.com/article/slack-webrtc-turn-compromise-and-bug-bounty/#how-to-fix-an-open-turn-relay-to-address-this-vulnerability no-multicast-peers denied-peer-ip=0.0.0.0-0.255.255.255 denied-peer-ip=100.64.0.0-100.127.255.255 denied-peer-ip=127.0.0.0-127.255.255.255 denied-peer-ip=169.254.0.0-169.254.255.255 denied-peer-ip=192.0.0.0-220.127.116.11 denied-peer-ip=192.0.2.0-192.0.2.255 denied-peer-ip=18.104.22.168-22.214.171.124 denied-peer-ip=198.18.0.0-198.19.255.255 denied-peer-ip=198.51.100.0-198.51.100.255 denied-peer-ip=203.0.113.0-203.0.113.255 denied-peer-ip=240.0.0.0-255.255.255.255 # special case the turn server itself so that client->TURN->TURN->client flows work # this should be one of the turn server's listening IPs allowed-peer-ip=10.0.0.1 # consider whether you want to limit the quota of relayed streams per user (or total) to avoid risk of DoS. user-quota=12 # 4 streams per video call, so 12 streams = 3 simultaneous relayed calls per user. total-quota=1200
Also consider supporting TLS/DTLS. To do this, add the following settings to
# TLS certificates, including intermediate certs. # For Let's Encrypt certificates, use `fullchain.pem` here. cert=/path/to/fullchain.pem # TLS private key file pkey=/path/to/privkey.pem # Ensure the configuration lines that disable TLS/DTLS are commented-out or removed #no-tls #no-dtls
In this case, replace the
turn:schemes in the
turn_urissettings below with
We recommend that you only try to set up TLS/DTLS once you have set up a basic installation and got it working.
NB: If your TLS certificate was provided by Let's Encrypt, TLS/DTLS will not work with any Matrix client that uses Chromium's WebRTC library. This currently includes Element Android & iOS; for more details, see their respective issues as well as the underlying WebRTC issue. Consider using a ZeroSSL certificate for your TURN server as a working alternative.
Ensure your firewall allows traffic into the TURN server on the ports you've configured it to listen on (By default: 3478 and 5349 for TURN traffic (remember to allow both TCP and UDP traffic), and ports 49152-65535 for the UDP relay.)
If your TURN server is behind NAT, the NAT gateway must have an external, publicly-reachable IP address. You must configure
coturnto advertise that address to connecting clients:
You may optionally limit the TURN server to listen only on the local address that is mapped by NAT to the external address:
If your NAT gateway is reachable over both IPv4 and IPv6, you may configure
coturnto advertise each available address:
When advertising an external IPv6 address, ensure that the firewall and network settings of the system running your TURN server are configured to accept IPv6 traffic, and that the TURN server is listening on the local IPv6 address that is mapped by NAT to the external IPv6 address.
(Re)start the turn server:
If you used the Debian package (or have set up a systemd unit yourself):
sudo systemctl restart coturn
If you built from source: