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[IDD #ZIL-446337]: aliased domain names

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  • Subject: [IDD #ZIL-446337]: aliased domain names
  • Date: Thu, 13 Nov 2008 11:21:36 -0700
> Jeff,
> 
> I'm trying to piece this together.  I am reasonably certain the easiest
> way will be to just change the domain names at all necessary locations,
> which are very few.  However, I'll take another shot at understanding
> what is happening.
> 
> The name of the server is:  sundowner.colorado.edu
> The alias (also the old) name of the server is:  foehn.colorado.edu
> The IP address of the server is:  128.138.136.10
> vardar is the local system from which I am running nslookup.
> -----------------------------------------------------------------
> 
> Doing an nslookup for sundowner:
> [seefeldm@vardar ~]$ nslookup sundowner.colorado.edu
> Server:         128.138.238.154
> Address:        128.138.238.154#53
> 
> Name:   sundowner.colorado.edu
> Address: 128.138.136.10
> 
> Doing an nslookup for foehn:
> [seefeldm@vardar ~]$ nslookup foehn.colorado.edu
> Server:         128.138.238.154
> Address:        128.138.238.154#53
> 
> foehn.colorado.edu      canonical name = sundowner.colorado.edu.
> Name:   sundowner.colorado.edu
> Address: 128.138.136.10
> 
> Doing a reverse nslookup on the IP address:
> [seefeldm@vardar ~]$ nslookup 128.138.136.10
> Server:         128.138.238.154
> Address:        128.138.238.154#53
> 
> 10.136.138.128.in-addr.arpa     name = sundowner.colorado.edu.
> 
> 
> The reverse lookup by doing an nslookup of the IP address does not go
> back to foehn.  This seems logical to me as the IP address should point
> to only one location, and this case foehn.  Does that make sense?  Is
> the fact that the IP address goes to sundowner and not the alias foehn,
> would that create problems for LDM to send and receive files?  I've
> discussed this with out sysadmin and he feels it doesn't make sense for
> a single IP address to point to two different domain names.  However, we
> are admittedly uncertain.
> 
> Thanks
> 
> Mark


Hi Mark,


Here is what we suggest you do:


Create a virtual interface on sundowner that has a unique IP address
for foehn.  That way it will have a unique forward/reverse DNS which the
remote LDM sites will need unless their allow entries are changed.

The construct (on Linux) will look something like;

   ifconfig eth0:1 128.138.136.<xxx> netmask <xxx> up

which will need to be propagated after subsequent systems re/boots.
 

..and if this is too much, we can always notify the other LDM's you connect 
to..to change the name from foehn to sundowner :)

Cheers,

Jeff 
Jeff Weber
Unidata User Support
http://www.unidata.ucar.edu

Ticket Details
===================
Ticket ID: ZIL-446337
Department: Support IDD
Priority: Normal
Status: Open