Main Issue is:
# systemctl status systemd-resolved.service
systemd-resolved.service -
Network Name Resolution Loaded: loaded (/lib/systemd/system/systemd-resolved.service; enabled; vendor preset: enabled)
Active: failed (Result: resources) since Wed 2021-05-19 11:15:15 UTC; 23s ago
Docs: man:systemd-resolved.service(8)
https://www.freedesktop.org/wiki/Software/systemd/resolved
https://www.freedesktop.org/wiki/Software/systemd/writing-network-configuration-managers
https://www.freedesktop.org/wiki/Software/systemd/writing-resolver-clients
May 19 11:15:15 kv-server systemd[1]: systemd-resolved.service: Service has no hold-off time, scheduling restart.
May 19 11:15:15 kv-server systemd[1]: systemd-resolved.service: Scheduled restart job, restart counter is at 5.
May 19 11:15:15 kv-server systemd[1]: Stopped Network Name Resolution.
May 19 11:15:15 kv-server systemd[1]: systemd-resolved.service: Start request repeated too quickly.
May 19 11:15:15 kv-server systemd[1]: systemd-resolved.service: Failed with result 'resources'.
May 19 11:15:15 kv-server systemd[1]: Failed to start Network Name Resolution.
This issue was something which I landed up by doing the below steps:
apt-get update
was failing. I started by following the answer of https://askubuntu.com/a/91590/1042537
This explained the issue and pointed fault towards DNS.
To configure dns servers, I followed https://stackoverflow.com/a/54460886/14950576 .
I also did # chattr +i /etc/resolv.conf
so that resolv.conf doesn't get updated by DHCP
I tried # ping google.com
but it still failed.
I observed a bad symlink /etc/resolv.conf -> /run/systemd/resolve/stub-resolve.conf
So I tried to access /run/systemd/resolve/stub-resolve.conf
Got an error that there is no directory /run/systemd/resolve
So I followed https://unix.stackexchange.com/a/613143 and got to know that systemd-resolved.service
was not running.
Error I got was
# systemctl enable --now systemd-resolved.service
Job for systemd-resolved.service failed because of unavailable resources or another system error.
See "systemctl status systemd-resolved.service" and "journalctl -xe" for details.
As I tried to do start that, I ran into the main issue.
So Network Name Resolution is unable to start.