fast DNS with two answers

Hi Erneri,

 

 

try the new version...

 

http://devcentral.f5.com/wiki/default.aspx/iRules/fast_DNS_2.html

 

 

what you need is customize static::domain and static::answer_string variable in RULE_INIT

 

 

Nat

Nat,

 

 

Thanks for your quick answer. I'll try to customize this irule with our custumer. Actually we resolved this with the next code

 

 

 

 

when RULE_INIT {

 

Header generation (in hexadecimal)

 

qr(1) opcode(0000) AA(1) TC(0) RD(1) RA(1) Z(000) RCODE(0000)

 

set ::header1 "8580"

 

set ::header2 "8580"

 

1 question, 1 answer, 0 NS, 0 Addition

 

set ::header1 "${::header1}0001000200000000"

 

set ::header2 "${::header2}0001000100000000"

 

Name = www.f5.com

 

set ::answer1 ""

 

set ::answer2 ""

 

 

Type = A

 

set ::answer1 "${::answer1}0001"

 

set ::answer2 "${::answer2}0001"

 

Class = IN

 

set ::answer1 "${::answer1}0001"

 

set ::answer2 "${::answer2}0001"

 

TTL = 1 day

 

set ::answer1 "${::answer1}00015180"

 

set ::answer2 "${::answer2}00015180"

 

Data length = 4

 

set ::answer1 "${::answer1}0004"

 

set ::answer2 "${::answer2}0004"

 

Address = 3.3.3.3

 

set ::answer1 "${::answer1}01010101"

 

set ::answer2 "${::answer2}02020202"

 

log local0. "match init"

 

}

 

when CLIENT_DATA {

 

binary scan [UDP::payload] H4@12A*@12H* id dname question

 

set dname [string tolower [getfield $dname \x00 1 ] ]

 

switch -glob $dname {

 

"\x03www\x02f5\x03com" {

 

set payload [binary format H* ${id}${::header1}${question}${::answer1}${::answer2} ]

 

drop

 

UDP::respond $payload

 

UDP::payload replace 0 0 $payload

 

}

 

default {

 

log local0. "does not match"

 

}

 

}

 

}

 

 

 

 

As soon as we test it, we´ll post our results

 

 

 

Thanks again

 

 

Regards

 

erneri

Hi erneri,

 

 

Are you on 10.x? If so, you can make the iRule CMP compatible by changing the global variables ($::header1, etc) to statics ($static::header1, etc).

 

 

http://devcentral.f5.com/wiki/default.aspx/iRules/CMPCompatibility.html

 

 

Aaron