Red Hat Summit Red Hat SummitSuporteConsoleDesenvolvedoresComeçar um testeContato

Este conteúdo não está disponível no idioma selecionado.

3.8. Enabling IP Multicast with IGMP

The Internet Group Management Protocol (IGMP) enables the administrator to manage routing and subscription to multicast traffic between networks, hosts, and routers. The kernel in Red Hat Enterprise Linux supports IGMPv3.
To display multicast information, use the ip maddr show subcommand, for example: 
~]$ ip maddr show dev br0
8:	br0
	inet  224.0.0.1
	inet6 ff02::1
	inet6 ff01::1
[output truncated]
Copy to Clipboard Toggle word wrap
Alternatively, look for the MULTICAST string in the ip link show command output, for example: 
~]$ ip link show br0
8: br0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP mode DEFAULT qlen 1000
    link/ether 6c:0b:84:67:fe:63 brd ff:ff:ff:ff:ff:ff
Copy to Clipboard Toggle word wrap
To disable multicast on a device and to check that multicast is disabled on the br0 device: 
~]# ip link set multicast off dev br0
~]$ ip link show br0
8: br0: <BROADCAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP mode DEFAULT qlen 1000
    link/ether 6c:0b:84:67:fe:63 brd ff:ff:ff:ff:ff:ff
Copy to Clipboard Toggle word wrap
The missing MULTICAST string indicates that multicast is disabled.
To enable multicast on the br0 device and to check it is enabled: 
~]# ip link set multicast on dev br0
~]$ ip link show br0
8: br0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP mode DEFAULT qlen 1000
    link/ether 6c:0b:84:67:fe:63 brd ff:ff:ff:ff:ff:ff
Copy to Clipboard Toggle word wrap
See the ip Command Cheat Sheet for Red Hat Enterprise Linux article and the ip(8) man page for more information.
To check current version of IGMP and IP addresses subscribed for multicasting, see the /proc/net/igmp file: 
~]$ cat /proc/net/igmp
Copy to Clipboard Toggle word wrap

Note

IGMP is not enabled in firewalld by default. To enable IGMP for a zone: 
~]# firewall-cmd --zone=zone-name --add-protocol=igmp
Copy to Clipboard Toggle word wrap
See the Using Firewalls chapter in the Red Hat Enterprise Linux Security Guide for more information.
Voltar ao topo
Red Hat logoGithubredditYoutubeTwitter

Aprender

Experimente, compre e venda

Comunidades

Sobre a documentação da Red Hat

Ajudamos os usuários da Red Hat a inovar e atingir seus objetivos com nossos produtos e serviços com conteúdo em que podem confiar. Explore nossas atualizações recentes.

Tornando o open source mais inclusivo

A Red Hat está comprometida em substituir a linguagem problemática em nosso código, documentação e propriedades da web. Para mais detalhes veja o Blog da Red Hat.

Sobre a Red Hat

Fornecemos soluções robustas que facilitam o trabalho das empresas em plataformas e ambientes, desde o data center principal até a borda da rede.

Theme

© 2025 Red Hat