Walking up DNS domain on SLES10

  • 7004131
  • 07-Aug-2009
  • 30-Apr-2012

Environment

Novell Open Enterprise Server 2 (OES 2) Linux
SUSE Linux Enterprise Server 10 Service Pack 1
SUSE Linux Enterprise Server 10 Service Pack 2
SUSE Linux Enterprise Server 11

Situation

Under Windows there is a functionality that will"walk up" the DNS domains when the default can not be resolved.

Unable to find in DNS a domain that is higher then your default domain.

Resolution

This is working as designed for SLES.

Additional Information

Windows resolver has some extra functionality to resolve hostnames and can perform a "walking up" the domain parts.

An example:
The configured domainname on a Windows XP workstation is room.loc1.country1.comp1.com
If the users needs mail.comp1.com and only enters e.g.: ping mail, the resolver of the workstation will start with resolving mail.room.loc1.country1.comp1.com, then mail.loc1.country1.comp1.com, then mail.country1.comp1.com, until it can resolv mail.comp1.com

The only way to achieve this partly on SLES is to use search parameter in the/etc/resolv.conf. When using search list for host-name lookup, the search list is normally determined from the local domain name; by default, it contains only the local domain name.  This may  be  changed  by  listing the desired domain search path following the search keyword with spaces or tabs separating the names.  Resolver queries having fewer than ndots dots (default is 1) in them will be attempted using each component  of  the search  path in turn until a  match is found.  For environments with multiple subdomains please read options ndots:n below to avoid man-in-the-middle attacks and unnecessary traffic for the root-dns-servers.  Note that this process may  be  slow  and will  generate  a lot of network traffic if the servers for the listed domains are not local, and that queries will time out if no server is available for one of the domains.

In this example search would have to look like:
search room.loc1.country1.comp1.com loc1.country1.comp1.com country1.comp1.com comp1.com