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lboogie25_20449's avatar
lboogie25_20449
Icon for Nimbostratus rankNimbostratus
Dec 13, 2015

Basic iRule

Sirs and Ma'ams:

 

I'm new to F5 (even newer to iRules) and I'm stuck on comprehending the operators/commands. What I'm trying to do is handle traffic from Linux machines and send to one pool while Windows machines go to a separate pool. The work requirement is done by TCP port. The iRule documentation is overwhelming at this point since I have no prior coding experience. The F5 returns an error "01070151:3: Rule [/Common/iRule-redirect-Test] error: /Common/iRule-redirect-Test:2: error: [missing a script after "if"][ ] /Common/iRule-redirect-Test:3: error: [parse error: PARSE missingBracket 84 {missing close-bracket}][{ [TCP::local_port == 80 }] /Common/iRule-redirect-Test:7: error: [missing a script after "if"][ ]"

 

Here is what I have:

 

when CLIENT_ACCEPTED { if { [IP::addr [IP::remote_addr] equals x.x.x.x/24] } if { [TCP::local_port == 80 } { pool HTTP-Pool } if { [IP::addr [IP::remote_addr] equals x.x.x.x/24] } if { [TCP::local_port] == 22} { pool SSH-Pool } }

 

application delivery
iRules
LTM
  • nathe's avatar
    nathe
    Icon for Cirrocumulus rankCirrocumulus
    Dec 13, 2015

    Lboogie25, looks like there's no ] after your first TCP::local_port == 80 command.

     

    This should sort but a word on your irule. As your first if statement is duplicated ie your checking the remote address, you could clean it up by using a nested if statement and using if/elseif.

     

    See https://devcentral.f5.com/articles/irules-101-13-nested-conditionals for what I mean.

     

    Hope this helps,

     

    N

     

  • lboogie25_20449's avatar
    lboogie25_20449
    Icon for Nimbostratus rankNimbostratus
    Dec 13, 2015

    Thanks for your help, Nathan. When I added the missing bracket, that didn't help. My TCP::local_port argument is incorrect. See error message: 01070151:3: Rule [/Common/iRule-redirect-Test] error: /Common/iRule-redirect-Test:2: error: [missing a script after "if"][ ] /Common/iRule-redirect-Test:3: error: [wrong args][TCP::local_port == 80] /Common/iRule-redirect-Test:7: error: [missing a script after "if"][ ]

     

    I guess what I'm struggling with are the available commands. Do you know where I can find a list of available arguments/variables to manipulate?

     

  • Mark_22062's avatar
    Mark_22062
    Icon for Nimbostratus rankNimbostratus
    Dec 14, 2015

    Because you are doing an if statement within an if statement I'd say you would need this:

     when CLIENT_ACCEPTED {
if { [IP::addr [IP::remote_addr] equals 192.168.1.1]}
{ if {[TCP::client_port equals 80} {pool Our-HTTP_Pool}}

if { [IP::addr [IP::remote_addr] equals 192.168.1.1]}
{ if {[TCP::client_port equals 22} {pool IRule-22-Test}}
}

    A more elegant way would be:

     when CLIENT_ACCEPTED {
if { [IP::addr [IP::remote_addr] equals 192.168.1.1]}
{ if {[TCP::client_port equals 80} {pool Our-HTTP_Pool}}
elseif {[TCP::client_port equals 22} {pool IRule-22-Test}
}

    You might want to consider what you want to do with traffic that doesn't match.

    • lboogie25_20449's avatar
      lboogie25_20449
      Icon for Nimbostratus rankNimbostratus
      Dec 16, 2015
      I tried this and it worked like a champ. Thanks for the tip on non-matching traffic. Many thanks for everyone's time!
  • Kai_Wilke's avatar
    Kai_Wilke
    Icon for MVP rankMVP
    Dec 14, 2015

    Hi Lboogie25,

    you may try this snippet if each pool needs a different IP address filter...

    when CLIENT_ACCEPTED { 
    if { [IP::addr [IP::remote_addr] equals x.x.x.x/24] and ([TCP::local_port] == 80) } then {
        pool HTTP-Pool
    } elseif { [IP::addr [IP::remote_addr] equals x.x.x.x/24] and ( [TCP::local_port] == 22 ) } then { 
        pool SSH-Pool 
    } 
}

    ... or if both pools using the same IP address filter, then try this snippet...

    when CLIENT_ACCEPTED { 
    if { [IP::addr [IP::remote_addr] equals x.x.x.x/24] {
        if { [TCP::local_port] == 80 } then {
            pool HTTP-Pool
        } elseif { [TCP::local_port] == 22 } then { 
            pool SSH-Pool 
        } 
    }
}

    Cheers, Kai