On Fri, May 24, 2024 at 11:13 AM Paul M Foster <pa...@quillandmouse.com> wrote: > > Folks: > > In my /etc/hosts file, there's a line: > > 127.0.1.1 yosemite.mars.lan yosemite > > I think Debian put it there. > > Later in the file, I've got: > > 192.168.254.30 yosemite.mars.lan yosemite > > So there are two entries for the same (my) machine. Is this a problem? > Specifically, could it cause problems with email (Exim4 or OpenSMTPD)?
127.0.1.1 is traditionally used for the fully qualified domain name (fqdn). So I would expect to see 'yosemite.mars.lan', but not 'yosemite'. Also, fqdn's end in dot '.' to denote the top of the dns tree. So I would expect to see 'yosemite.mars.lan.' (note the trailing dot), and not 'yosemite.mars.lan' (note the lack of the trailing dot). What can happen with 'yosemite.mars.lan' is, search domains can be added to it. So if dhcp says 'isp.com' is a search domain, then your network stack might make requests for 'yosemite.mars.lan.isp.com'. Jeff
