Mar 27, 2026 - For details about updated CVE-2025-53521 (BIG-IP APM vulnerability), refer to K000156741.

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brwalk0069's avatar
brwalk0069
Icon for Nimbostratus rankNimbostratus
Sep 09, 2019

iRule to set recursion on DNS request

Hi guys,

Wondered if anyone had experience of or knows of a resource online for how to set the recursion flag on a DNS request?

I'm forwarding the DNS request based on domain with another iRule but the recursion flag must be set or it doesn't work.

Any advice would be much appreciated!

1 Reply

  • brwalk0069's avatar
    brwalk0069
    Icon for Nimbostratus rankNimbostratus
    Sep 10, 2019

    Incase anyone is interested I managed to get an iRule working for this;

    when DNS_REQUEST {
  if { [DNS::header rd] eq "0" } {
    DNS::header rd 1
  }
}

    Cheers