rlogin sometimes hangs (from FC6 client)

[Eur Ing Chris Green]

On Thu, Mar 15, 2007 at 01:04:08PM +0000, replies-lists-a1z2-redhat at listmail.innovate.net wrote:
> 
> 
> >> > Date: Thursday, March 15, 2007 11:24:13 AM +0000
> >> > From: Eur Ing Chris Green <cl at isbd.net>
> >> > To: fedora-list at redhat.com
> >> > Subject: rlogin sometimes hangs (from FC6 client)
> >> > 
> >> > I have just moved to Fedora Core 6 on my desktop computer at work.
> >> > We have a mixed environment of Windows PCs a few Linux ones and a
> >> > number of Solaris target systems.
> >> > 
> >> > When I rlogin from my new FC6 system to the Solaris systems the
> >> > login sometimes just hangs, i.e. I type "rlogin crusade" and
> >> > nothing happens for several minutes then I get a timeout message.
> >> > 
> >> > This seems to happen only on the FC6 systems, I have tried it from
> >> > one other FC6 system and it's the same but from a kubuntu
> >> > installation (on the same sub-net) it doesn't happen.  The rlogin
> >> > hangs maybe one time in four or so, the other times it connects
> >> > normally and works OK from then on.
> >> >  
> >> > Does anyone have any ideas what might be causing this problem?
> >> 
> >> this is generally a dns issue.
> >> 
> >> the remote host tries to do a lookup of the inbound ipnumber. if
> >> there isn't an in-addr.arpa entry for the ipnumber you'll get a
> >> delay (which may be long enough for a timeout). additionally, if
> >> access control on the remote system is by inbound hostname (which is
> >> determined by a lookup against the inbound ipnumber), rather than
> >> ipnumber, a lookup failure will result in your not getting access.
> >> 
> >> note, this is the a dns lookup on the *ipnumber* of your fc6 system,
> >> not a lookup by that machine's hostname.
> >> 
> > Hmmm.  This is all on a 10.x.x.x intranet at work.  It uses NIS/YP for
> > internal lookup and, as far as I can see, the systems in question all
> > seem to be properly entered in the NIS database.
> > 
> 
> on the remote system that you're trying to log in to try doing a dns
> lookup of the ipnumber of the source machine and see what you get.
> 
All 'dns' lookups for 'internal' systems fail, the only lookup tool
on Solaris is nslookup and that specifically does a nameserver
lookup and there's no 'internal' nameserver, everything gets found
by using NIS.  If I (for example) ping the IP address of the FC6
system from the Solaris system it always succeeds - well I did 100 or
so and they all worked.

-- 
Chris Green