All-
My site happens to use mixed case in the DNS domain name, and over the
years I've noted some strange behavior on occassion out of our Digital/Tru64
UNIX boxes because of this. None of our other UNIX platforms (Solaris, AIX,
HP-UX, IRIX, Linux, et. al.) have any problems with mixed case in the
DNS domain name that I've been able to find.
I got bit by the problem again tonight, with /etc/syslog.auth, and it
was enough for me to finally ask if other sites that use mixed case in the
DNS domain name have noticed the same problems?
A couple of places where I've seen the problem:
1) a couple years ago, when we upgraded a few of our (then) Digital UNIX
boxes to NetWorker 5.2, we immediately began having problems with `savefs'
reporting "nothing to save". Working with Digital and then later Legato
we were able to track the problem to the mixed case domain name. A friend
that used to work at Legato told me at one point that they thought they
had it fixed, but it's still present to this day. The only two workarounds
are either to not used mixed case in the domain name (difficult, for
many non-technical reasons) or not use the "All" wildcard for what filesystems
to backup, which can become a (dangerous, error-prone) management headache.
2) syslog on Tru64 through at least 4.x will not resolve FQDNs that use
mixed case in the /etc/hosts entry (resolver order must be set to local,bind
to be able to test this) if you don't use exactly the same text when
trying to use the host.
3) ditto for telnet, and possibly other tools
How to reproduce:
1) Make sure your /etc/svc.conf has
hosts=local,bind
(Only do this for testing, if you don't want resolver lookups to use
/etc/hosts first!)
2) You may want to change /etc/svcorder to be
local
bind
(that file doesn't exist on 5.x, no idea which bits use it on 4.x, but
both it and /etc/svc.conf get set up when you set up DNS to use local
first).
3) Edit your /etc/hosts so that on your
127.0.0.1 localhost
line you have instead:
127.0.0.1 localhost foo.DoesNotExist.com
4) now try
/usr/bin/telnet foo.doesnotexist.com
if the problem happens for you, you'll get:
foo.doesnotexist.com: Unknown host
if, however, you type:
/usr/bin/telnet foo.DoesNotExist.com
you'll be connected over the loopback.
Similar test cases can be constructed using remote host logging via
_at_server.domain.com
in /etc/syslog.conf, and even in /etc/syslog.auth.
In each case, Digital/Tru64 doesn't correctly resolve mixed case DNS entries
unless you also specify the case exactly the same when using it.
According to my reading of the RFCs (and how the other platforms perform),
this is wrong.
Any other mixed-case sites see the same, and agree that the behavior is
wrong and should be fixed?
Tim
--
Tim Mooney mooney_at_dogbert.cc.ndsu.NoDak.edu
Information Technology Services (701) 231-1076 (Voice)
Room 242-J1, IACC Building (701) 231-8541 (Fax)
North Dakota State University, Fargo, ND 58105-5164
Received on Thu Sep 14 2000 - 06:44:22 NZST