DNS reverse lookup behavior

[acovington]

/etc/netsvc.conf contains "hosts=local"
no /etc/named.* files exist
no /etc/resolv.* files exist
AIX version 4.3.3

I have an application uses ODBC and Visual Basic programs to communicate to an Informix database on my RS/6000. Apparently, some part of this application performs a reverse lookup during the login process. When this occurs, one of my Windows servers logs the traffic - a reverse lookup request, coming from the IP address of my RS/6000. Trouble is, it's the wrong server! It can't fulfill the request, and causes headaches for me and my application. The application vendor says that they aren't doing anything except making normal system calls, and that AIX "must have a problem".

When I attempt a reverse lookup from the shell prompt, using the "HOST" command or Perl scripts, there is no traffic generated to the Windows server and it is obviously using only the information in /etc/hosts - as I'd expect with my /etc/netsvc.conf configuration.

Where else can I look? Where else might my incorrect Windows server be referred to in AIX? Thanks for any ideas.

 

[Chapter11]

It's probably informix that's making the request. DNS service is generally one of the few things that's "assumed" to exist on a unix system. Informix will be making the call, not necessarily AIX, and so AIX will try to fulfill it.

The best I can suggest is to go ahead and create a /etc/resolv.conf that will point to a server that can answer the request.

 

[acovington]

Thanks for the idea, but I've tried creating the /etc/resolv.conf, and something is still trying to use the wrong Windows server. Any other ideas?

 

[AIXSPadmin]

Did you check /etc/hosts?

 

[sectorseveng]

Does the application user have the NSORDER environment variable set? - check with env
Does the application user issue the nslookup command? - check via auditing, or you could change permissions/name of nslookup and see which process sqawks.