server configuration

[Danny Mayer]

At 05:50 PM 1/5/01, Sheer El-Showk wrote:

>Hi,
>
>I am trying to plan a DNS configuration that will support a large number
>of zones (possibly hundreds of thousands) and a commiserate number of
>queries.  From what I have been able to glean from various FAQ's and
>Dr. DNS, the limiting factor in a server's ability to serve domains is
>memory (needing to laod the zone files in memory or in a data structure).
>
>Does anyone have experience with large scale DNS setups.  Could someone
>suggest what the saturation point (bandwidth aside) of an intel server
>class PC would be (1 GHz, 1 Gig RAM, U2W SCSI, etc...).  Obviously there
>are many variables so real examples would probably be most useful.

         I know someone running 30K plus domains on a P-III 550Mhz machine
   running Win2K.  Works fine.

>Also, Dr. DNS says BIND has no hard-coded maximum number of zones.  Can
>anyone confirm this (someone told me that ~65k -- 16 bit number -- zones
>was a hard limit -- might this have been a kernel open file handles limit
>or something like that).  Also, what other (non-BIND) considerations might
>there be if one is talking about hundreds of thousands of zones -- open
>file descriptors is certainly one -- anything else?

         The TLD's have to deal with the .com domain that numbers in the millions
   and they don't have trouble dealing with them.  The files on disk are basically
   loaded one at a time as it reads through the named.conf file.  Once each file is
   loaded it closed the file and goes on to the next, so it doesn't need more than
   a few file descriptors open simultaneously.  Sockets are a more important factor
   but you usually don't have many interfaces that you are listening on and
   responding to simultaneously.

>I'm an avid Linux user, but does anything have a reason to suggest that
>Linux might not be a viable platform for this scale of deployement
>(specifics, not just "Linux is not enterprise ready" ;->)?
         Your mileage may vary.

                 Danny