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Chapter 34. Manually configuring the /etc/resolv.conf file

By default, NetworkManager on Red Hat Enterprise Linux (RHEL) 8 dynamically updates the /etc/resolv.conf file with the DNS settings from active NetworkManager connection profiles. This section describes different options on how to disable this feature to manually configure DNS settings in /etc/resolv.conf.

34.1. Disabling DNS processing in the NetworkManager configuration

This section describes how to disable DNS processing in the NetworkManager configuration to manually configure the /etc/resolv.conf file.

Procedure

  1. As the root user, create the /etc/NetworkManager/conf.d/90-dns-none.conf file with the following content by using a text editor: 

    [main]
dns=none

  2. Reload the NetworkManager service: 

    # systemctl reload NetworkManager
    Note

    After you reload the service, NetworkManager no longer updates the /etc/resolv.conf file. However, the last contents of the file are preserved.

  3. Optionally, remove the Generated by NetworkManager comment from /etc/resolv.conf to avoid confusion.

Verification steps

  1. Edit the /etc/resolv.conf file and manually update the configuration.

  2. Reload the NetworkManager service: 

    # systemctl reload NetworkManager

  3. Display the /etc/resolv.conf file: 

    # cat /etc/resolv.conf

    If you successfully disabled DNS processing, NetworkManager did not override the manually configured settings.

Additional resources

  • The dns parameter description in the NetworkManager.conf(5) man page