Re: [gentoo-user] resolving names of local hosts locally

[Rich Freeman]

On Wed, Dec 16, 2015 at 4:26 AM, Alan McKinnon <alan.mckinnon@×××××.com> wrote:
>
> Solution: obey best practice. Never run auth and cache on the same
> address. On the same machine is fine, they are different daemons.
>

Which one listens on port 53?  Also, how do you point the caching
daemon at the authoritative daemon for internal servers/domains/etc?
My authoritative server for doubleclick.net is not the same as the one
you'll find in the .net servers.  Also, for the domains I use
internally the DNS server and resolution is different within my LAN
from what you'd see on the internet.  I know that at my employer
internal DNS resolution is not the same as what you'd find outside the
organization, so this isn't an issue unique to small setups.

One of the reasons I run auth and cache on the same host is that it
greatly simplifies dependencies.  If I want to run them on separate
containers then they'll either need static addresses, or need to use
DHCP, which means the DHCP server has a potential circular dependency
with the DNS servers.  Plus most of my containers are going to need
DNS so these containers need to be running before other containers get
started.

For a large-scale datacenter the separated approach makes a lot of
sense.  If you're running 5000 hosts having two (or likely 10 counting
various backups/etc) that you start first isn't a big deal, and
neither is dedicating a bit of hardware to DNS/DHCP.  If you're
running all your services on one host, it can get a bit messy when you
start having multiple DNS servers all running on different IPs on the
same host.  It can of course still be done.

I just use BIND for both.  It isn't the best solution, but it is adequate.

-- 
Rich