sonic-buildimage/files/image_config/resolv-config/resolv.conf.head

# Dynamic resolv.conf(5) file generated by resolvconf(8)
# The content of this file may be overwritten during a config reload.
Clear DNS configuration received from DHCP during networking reconfiguration in Linux. (#13516) - Why I did it fixes #12907 When the management interface IP address configuration changes from dynamic to static the DNS configuration (retrieved from the DHCP server) in /etc/resolv.conf remains uncleared. This leads to a DNS configuration pointing to the wrong nameserver. To make the behavior clear DNS configuration received from DHCP should be cleared. - How I did it Use resolvconf package for managing DNS configuration. It is capable of tracking the source of DNS configuration and puts the configuration retrieved from the DHCP servers into a separate file. This allows the implementation of DNS configuration cleanup retrieved from DHCP during networking reconfiguration. - How to verify it Ensure that the management interface has no static configuration. Check that /etc/resolv.conf has DNS configuration. Configure a static IP address on the management interface. Verify that /etc/resolv.conf has no DNS configuration. Remove the static IP address from the management interface. Verify that /etc/resolv.conf has DNS configuration retrieved form DHCP server. 2023-01-30 14:13:10 -06:00			`# Dynamic resolv.conf(5) file generated by resolvconf(8)`
			`# The content of this file may be overwritten during a config reload.`