Skip to content

Enable multicast on lo#

Manually (temporary solution)#

You may just call the following command to enable multicast on the loopback interface.

sudo ip link set lo multicast on

Warning

This will be reverted once the computer restarts. To make it permanent, follow the steps below.

Note

Here, lo is the loopback interface.

You can check the interfaces with ip link show.

You may change lo with the interface you want to enable multicast on.

On startup with a service (permanent solution)#

sudo nano /etc/systemd/system/multicast-lo.service

Paste the following into the file:

[Unit]
Description=Enable Multicast on Loopback

[Service]
Type=oneshot
ExecStart=/usr/sbin/ip link set lo multicast on

[Install]
WantedBy=multi-user.target

Press following in order to save with nano:

  1. Ctrl+X
  2. Y
  3. Enter
# Make it recognized
sudo systemctl daemon-reload

# Make it run on startup
sudo systemctl enable multicast-lo.service

# Start it now
sudo systemctl start multicast-lo.service

Validate#

you@pc:~$ sudo systemctl status multicast-lo.service
○ multicast-lo.service - Enable Multicast on Loopback
     Loaded: loaded (/etc/systemd/system/multicast-lo.service; enabled; vendor preset: enabled)
     Active: inactive (dead) since Mon 2024-07-08 12:54:17 +03; 4s ago
    Process: 22588 ExecStart=/usr/bin/ip link set lo multicast on (code=exited, status=0/SUCCESS)
   Main PID: 22588 (code=exited, status=0/SUCCESS)
        CPU: 1ms

Tem 08 12:54:17 mfc-leo systemd[1]: Starting Enable Multicast on Loopback...
Tem 08 12:54:17 mfc-leo systemd[1]: multicast-lo.service: Deactivated successfully.
Tem 08 12:54:17 mfc-leo systemd[1]: Finished Enable Multicast on Loopback.

you@pc:~$ ip link show lo
1: lo: <LOOPBACK,MULTICAST,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00

Uninstalling the service#

If for some reason you want to uninstall the service, you can do so by following these steps:

# Stop the service
sudo systemctl stop multicast-lo.service

# Disable the service from running on startup
sudo systemctl disable multicast-lo.service

# Remove the service file
sudo rm /etc/systemd/system/multicast-lo.service

# Reload systemd to apply the changes
sudo systemctl daemon-reload