Why are IPV6 DNS lookups done even when IPV6 is disabled in Red Hat Enterprise Linux?

Solution Verified - Updated -


  • Applications like ssh and telnet use the getaddrinfo() function with AF_UNSPEC and this function invokes both AAAA (IPv6) and A (IPv4) lookups one after the other. This can delay the connection time when DNS servers block or don't handle IPV6 correctly.


  • Red Hat Enterprise Linux 4
  • Red Hat Enterprise Linux 5
  • Red Hat Enterprise Linux 6
  • Red Hat Enterprise Linux 7
  • glibc

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