[7990] in testers
Re: odd problem with domain resolution on Athena 10
daemon@ATHENA.MIT.EDU (Anders Kaseorg)
Fri Apr 3 16:46:40 2009
Date: Fri, 3 Apr 2009 16:46:11 -0400 (EDT)
From: Anders Kaseorg <andersk@MIT.EDU>
To: Alex T Prengel <alexp@mit.edu>
cc: debathena@mit.edu, testers@mit.edu
In-Reply-To: <200904032035.n33KZAKQ014792@dit.mit.edu>
Message-ID: <alpine.DEB.2.00.0904031638000.6942@vinegar-pot.mit.edu>
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On Fri, 3 Apr 2009, Alex T Prengel wrote:
> 127.0.1.1 zippy zippy.mit.edu
> is denied, but
> 127.0.1.1 zippy.mit.edu
> is allowed.
This probably happens because `hostname -i` will be 127.0.1.1 in the
former case, but 18.142.4.128 in the latter case. So this is another
manefestation of the known problem with 127.0.1.1.
(The way this works is:
* An initscript sets the kernel’s hostname from /etc/hostname at boot;
* `hostname` is the kernel’s hostname;
* `hostname -i` is the IP address resolved from `hostname`;
* `hostname -f` is the name reverse-resolved from `hostname -i`;
* `hostname -d` is everything but the first component of `hostname -f`.)
Anders
