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Found sudo not working for all command and got error:
sudo: unable to resolve host ubdev
ubdev is my current hostname.
The sudo is still working and but taking long time.
Finally the issue is on /etc/hosts, hostname mismatch with real hostname after last time I changed hostname from ubuntu to ubdev.
127.0.0.1 localhost 127.0.1.1 ubuntu
change ubuntu to ubdev, sudo back to normal.