Why are reverse host lookup request not being cached by the Name Service Caching Daemon (nscd)?

Solution Unverified - Updated -


  • On a few busy web servers (RHEL 6.5) we see a lot of DNS PTR lookups for a few hostnames
  • If possible, we would like to limit the number of DNS lookups, but it doesn’t look like nscd is caching reverse lookups like it does forward lookups
  • Is it possible to configure nscd to also cache PTR lookups, or are you aware of another solution for this (adding the hosts to /etc/hosts is not a solution)?


  • Red Hat Enterprise Linux (RHEL) all supported version

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