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f5_rocks's avatar
f5_rocks
Icon for Nimbostratus rankNimbostratus
May 06, 2016
Solved

Trying to correctly fformat multiple not statements

started with this... 

when CLIENT_ACCEPTED {event HTTP_REQUEST enable}
when HTTP_REQUEST {
  set MY_HOST [string tolower [HTTP::host]]
  set MY_URI [string tolower [HTTP::uri]]

  if {$MY_URI starts_with "/abcd/web/abcd.client.web/"} { 
      if {$MY_HOST equals "m3.companyname.com"} {
      HTTP::redirect http://a1.m3.companyname.com$MY_URI
      } elseif {$MY_HOST equals "internal.m3.companyname.com"} {
      HTTP::redirect http://internal.a1.m3.companyname.com$MY_URI
      } elseif {$MY_HOST equals "internal.m3-dc1.companyname.com"} {
      HTTP::redirect http://internal.a1.m3-dc1.companyname.com$MY_URI
      } elseif {$MY_HOST equals "internal.m3-dc2.companyname.com"} {
      HTTP::redirect http://internal.a1.m3-dc2.companyname.com$MY_URI
      } elseif {$MY_HOST equals "internal.m3-dc3.companyname.com"} {
      HTTP::redirect http://internal.a1.m3-dc3.companyname.com$MY_URI
      }
  event HTTP_REQUEST disable
  TCP::close
}
}
when HTTP_RESPONSE {event HTTP_REQUEST enable}
===================================================================

tried using use "or", f5 accepted it as syntactically correct, but this try didn't work, still redirected the "not" uris...

when CLIENT_ACCEPTED {event HTTP_REQUEST enable}
when HTTP_REQUEST {
  set MY_HOST [string tolower [HTTP::host]]
  set MY_URI [string tolower [HTTP::uri]]

  if {$MY_URI starts_with "/abcd/"} { 
   if {not ($MY_URI starts_with "/abcd/web/abcdpayment.web/") or not ($MY_URI starts_with "/abcd/web/abcdpaymentprocessing.web/")} {
    if {$MY_HOST equals "m3.companyname"} {
    HTTP::redirect http://a1.m3.companyname$MY_URI
    } elseif {$MY_HOST equals "internal.m3.companyname"} {
    HTTP::redirect http://internal.a1.m3.companyname$MY_URI
    } elseif {$MY_HOST equals "internal.m3-dc1.companyname"} {
    HTTP::redirect http://internal.a1.m3-dc1.companyname$MY_URI
    } elseif {$MY_HOST equals "internal.m3-dc2.companyname"} {
    HTTP::redirect http://internal.a1.m3-dc2.companyname$MY_URI
    } elseif {$MY_HOST equals "internal.m3-dc3.companyname"} {
    HTTP::redirect http://internal.a1.m3-dc3.companyname$MY_URI
    }
  event HTTP_REQUEST disable
  TCP::close
  }
}
}
when HTTP_RESPONSE {event HTTP_REQUEST enable}
devops
iRules
  • Vernon_97235's avatar
    Vernon_97235
    May 07, 2016

    not or not
    probably doesn't mean what you think. Consider 
    not A or not B
    . Assuming that A, B and C are mutually exclusive conditions, the statement 
    not A or not B
    is true under all of the following conditions:

    • A is true
    • B is true
    • C is true

    That's because 

    not A or not B
    is true if: A is not true, if B is not true, or if both are not true. In the first case (
    A is true
    ), B is not true, so the statement matches. In the second case (
    B is true
    ), A is not true, so the statement matches. In the third case, both A and B are not true, so the statement matches. Putting this in terms of your command, consider:

    not ($MY_URI starts_with "/abcd/web/abcdpayment.web/") or not ($MY_URI starts_with "/abcd/web/abcdpaymentprocessing.web/")

    If 

    $MY_URI
    starts_with "/abcd/web/abcdpayment.web/" this statement actually matches (that is, it evaluates to true) because the condition 
    not ($MY_URI starts_with "/abcd/web/abcdpaymentprocessing.web/")
    is in fact true: 
    $MY_URI
    does NOT start with "/abcd/web/abcdpaymentprocessing.web/".

    You want 

    not and not
    . Consider 
    not A and not B
    . According to this:

    • if A is true, the statement is false (because 
      not A
      is false)
    • if B is true, the statement is false (because 
      not B
      is false)
    • if C is true, the statement is true (because 
      not A
      is true and 
      not B
      is true)

    Again, matching against your logic:

    not ($MY_URI starts_with "/abcd/web/abcdpayment.web/") and not ($MY_URI starts_with "/abcd/web/abcdpaymentprocessing.web/")

    Now, if 

    $MY_URI
    starts with "/abcd/web/abcdpayment.web/", this statement is false.

    Incidentally, this is exactly equivalent to:

    not ($MY_URI starts_with "/abcd/web/abcdpayment.web/" or $MY_URI starts_with "/abcd/web/abcdpaymentprocessing.web/")

4 Replies

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  • Vernon_97235's avatar
    Vernon_97235
    Historic F5 Account
    May 07, 2016

    not or not
    probably doesn't mean what you think. Consider 
    not A or not B
    . Assuming that A, B and C are mutually exclusive conditions, the statement 
    not A or not B
    is true under all of the following conditions:

    • A is true
    • B is true
    • C is true

    That's because 

    not A or not B
    is true if: A is not true, if B is not true, or if both are not true. In the first case (
    A is true
    ), B is not true, so the statement matches. In the second case (
    B is true
    ), A is not true, so the statement matches. In the third case, both A and B are not true, so the statement matches. Putting this in terms of your command, consider:

    not ($MY_URI starts_with "/abcd/web/abcdpayment.web/") or not ($MY_URI starts_with "/abcd/web/abcdpaymentprocessing.web/")

    If 

    $MY_URI
    starts_with "/abcd/web/abcdpayment.web/" this statement actually matches (that is, it evaluates to true) because the condition 
    not ($MY_URI starts_with "/abcd/web/abcdpaymentprocessing.web/")
    is in fact true: 
    $MY_URI
    does NOT start with "/abcd/web/abcdpaymentprocessing.web/".

    You want 

    not and not
    . Consider 
    not A and not B
    . According to this:

    • if A is true, the statement is false (because 
      not A
      is false)
    • if B is true, the statement is false (because 
      not B
      is false)
    • if C is true, the statement is true (because 
      not A
      is true and 
      not B
      is true)

    Again, matching against your logic:

    not ($MY_URI starts_with "/abcd/web/abcdpayment.web/") and not ($MY_URI starts_with "/abcd/web/abcdpaymentprocessing.web/")

    Now, if 

    $MY_URI
    starts with "/abcd/web/abcdpayment.web/", this statement is false.

    Incidentally, this is exactly equivalent to:

    not ($MY_URI starts_with "/abcd/web/abcdpayment.web/" or $MY_URI starts_with "/abcd/web/abcdpaymentprocessing.web/")
    • f5_rocks's avatar
      f5_rocks
      Icon for Nimbostratus rankNimbostratus
      May 07, 2016
      I understand. The first example with the "and not", made it clear. Thanks.
  • VernonWells's avatar
    VernonWells
    Icon for Employee rankEmployee
    May 07, 2016

    not or not
    probably doesn't mean what you think. Consider 
    not A or not B
    . Assuming that A, B and C are mutually exclusive conditions, the statement 
    not A or not B
    is true under all of the following conditions:

    • A is true
    • B is true
    • C is true

    That's because 

    not A or not B
    is true if: A is not true, if B is not true, or if both are not true. In the first case (
    A is true
    ), B is not true, so the statement matches. In the second case (
    B is true
    ), A is not true, so the statement matches. In the third case, both A and B are not true, so the statement matches. Putting this in terms of your command, consider:

    not ($MY_URI starts_with "/abcd/web/abcdpayment.web/") or not ($MY_URI starts_with "/abcd/web/abcdpaymentprocessing.web/")

    If 

    $MY_URI
    starts_with "/abcd/web/abcdpayment.web/" this statement actually matches (that is, it evaluates to true) because the condition 
    not ($MY_URI starts_with "/abcd/web/abcdpaymentprocessing.web/")
    is in fact true: 
    $MY_URI
    does NOT start with "/abcd/web/abcdpaymentprocessing.web/".

    You want 

    not and not
    . Consider 
    not A and not B
    . According to this:

    • if A is true, the statement is false (because 
      not A
      is false)
    • if B is true, the statement is false (because 
      not B
      is false)
    • if C is true, the statement is true (because 
      not A
      is true and 
      not B
      is true)

    Again, matching against your logic:

    not ($MY_URI starts_with "/abcd/web/abcdpayment.web/") and not ($MY_URI starts_with "/abcd/web/abcdpaymentprocessing.web/")

    Now, if 

    $MY_URI
    starts with "/abcd/web/abcdpayment.web/", this statement is false.

    Incidentally, this is exactly equivalent to:

    not ($MY_URI starts_with "/abcd/web/abcdpayment.web/" or $MY_URI starts_with "/abcd/web/abcdpaymentprocessing.web/")
    • f5_rocks's avatar
      f5_rocks
      Icon for Nimbostratus rankNimbostratus
      May 07, 2016
      I understand. The first example with the "and not", made it clear. Thanks.