Errors Updating/Installing Bind9 on Ubuntu

If you encounter errors such as:

dpkg: error processing package bind9 (--configure):
subprocess installed post-installation script returned error exit status 1
Errors were encountered while processing:
bind9

This is typical due to the Linux kernel security module apparmor. The easiest way to get round this error, is to stop apparmor, then install bind9, as follows:

sudo service apparmor stop
sudo service apparmor teardown

Then:

sudo apt-get install bind9

OR:

sudo apt-get upgrade bind9