I’ve noticed if you do a full BIND reload from webmin from a zone page the page gets stuck seemingly repeatedly freezing and thawing the currently-viewed zone:
Feb 9 00:33:29 l03 named[4897]: received control channel command 'freeze example.com'
Feb 9 00:33:30 l03 named[4897]: received control channel command 'reload example.com'
Feb 9 00:33:31 l03 named[4897]: received control channel command 'thaw example.com'
Feb 9 00:33:31 l03 named[4897]: thawing zone 'example.com/IN': success
Feb 9 00:33:32 l03 named[4897]: received control channel command 'freeze example.com'
Feb 9 00:33:33 l03 named[4897]: received control channel command 'reload example.com'
Feb 9 00:33:35 l03 named[4897]: received control channel command 'thaw example.com'
Feb 9 00:33:35 l03 named[4897]: thawing zone 'example.com/IN': success
…etc
To do this, go to BIND DNS Server -> click any zone and hit reload config on that page. Watch the progress slider constantly animate along the top of the page as well. /var/log/messages shows the reload begins OK, but gets stuck for ages doing this.
Clicking on BIND DNS Server (or any other Webmin page) escapes the loop, but it’s not immediately obvious that it’s not reloading normally.