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jrmorris_151361's avatar
jrmorris_151361
Icon for Nimbostratus rankNimbostratus
Dec 23, 2014

DNS:rrtype undefined procedure

I am trying to create the following iRule to help rate limit DNS queries for amplification protection as noted in a few articles. But I get an undefined error. I've confirmed DNS:rrtype is a good var...
application delivery
devops
iRules
jrmorris_151361's avatar
jrmorris_151361
Icon for Nimbostratus rankNimbostratus
Dec 23, 2014

Thanks. Should I be doing this on GTM instead? I was going to apply it to to the LTM VIPs so I could apply the rate class. I do have active GTM licenses.

Thanks.

Also...does this look correct?

when DNS_REQUEST {
  if { ([DNS::type $rr] == "TXT") } {
     rateclass dns_rate_shape
     }
}

when DNS_RESPONSE {
  if { [DNS::len] > 512 } {
     rateclass dns_rate_shape
     }
}