resolver timeout + application timeout : LDAP and slow prim. nameserver ..

[Claus van de Vlierd]

  Hello ,

   a) our LDAP- and Sendmail-Applicationserver (RedHat AS3) have in
       their "/etc/resolv.conf" -  Files :

        "<IP-address of primary nameserver>"
        "<IP-address of secondary nameserver>" .

   b) unfortunately sometimes our prim. nameserver answers rather slowly 

      and even more unfortunately : in those cases the
       LDAP- and Sendmail-Server do NOT switch to the
       (still repidly working) sec. nameserver .

       (our Browsers like "Netscape"  have no problem to use the sec. 
Nameserver
         as soon as the primary becomes slow ..) .

   c) HOW can we change that (besides of course making the prim. nameserver
    quicker ..) ?!

    is there any possibility in the "/etc/resolv.conf" (under RedHat AS3) to
    give a "timeout" shorter than the timeout for the application
     (like e.g. "sendmail") so that the application "has still time"  to 
switch
     to the sec. nameserver ?!

     d) any hint would be appreciated  how to induce our LDAP- and
       Sendmail-Server to use the sec. NS in case of need .. !

    e) thanx and regards :

       Claus van de Vlierd