Chapter 17. Configuring the DHCP timeout behavior of a NetworkManager connection

Procedure

1. Optional: Set the ipv4.dhcp-timeout and ipv6.dhcp-timeout properties. For example, to set both options to 30 seconds, enter:

   # nmcli connection modify <connection_name> ipv4.dhcp-timeout 30 ipv6.dhcp-timeout 30

   Alternatively, set the parameters to infinity to configure that NetworkManager does not stop trying to request and renew an IP address until it is successful.

2. Optional: Configure the behavior if NetworkManager does not receive an IPv4 address before the timeout:

   # nmcli connection modify <connection_name> ipv4.may-fail <value>

   If you set the ipv4.may-fail option to:

   • yes, the status of the connection depends on the IPv6 configuration:

     • If the IPv6 configuration is enabled and successful, NetworkManager activates the IPv6 connection and no longer tries to activate the IPv4 connection.
     • If the IPv6 configuration is disabled or not configured, the connection fails.

   • no, the connection is deactivated. In this case:

     • If the autoconnect property of the connection is enabled, NetworkManager retries to activate the connection as many times as set in the autoconnect-retries property. The default is 4.
     • If the connection still cannot acquire a DHCP address, auto-activation fails. Note that after 5 minutes, the auto-connection process starts again to acquire an IP address from the DHCP server.

3. Optional: Configure the behavior if NetworkManager does not receive an IPv6 address before the timeout:

   # nmcli connection modify <connection_name> ipv6.may-fail <value>