Howto update the Root Hints file for BIND Named server in Ubuntu or Debian?

Ubuntu Linux:

You can retrieve root zone file from ftp://ftp.rs.internic.net.

wget –user=ftp –password=ftp ftp://ftp.rs.internic.net/domain/db.cache -O /etc/bind/db.root

Reload rndc to update information, enter:
rndc reload

Another option is run dig command to fetch information:
# dig +bufsize=1200 +norec NS . @a.root-servers.net > /etc/bind/db.root