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

Forum Discussion

hoolio's avatar
hoolio
Icon for Cirrostratus rankCirrostratus
Nov 24, 2008

Evaluate command only at runtime--not RULE_INIT?

Hi there, I'd like to set a variable in RULE_INIT which contains the command HTTP::host and then have it evaluated at runtime in HTTP_REQUEST: when RULE_INIT { set ::htm...
application delivery
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hoolio's avatar
hoolio
Icon for Cirrostratus rankCirrostratus
Nov 24, 2008
Nevermind... escaping the braces of [HTTP::host] and [HTTP::uri] in RULE_INIT and then using subst in HTTP_REQUEST works: 

    
 when RULE_INIT { 
  
     Trigger a meta-refresh every X seconds 
    set ::refresh_interval 30 
  
     HTML content containing meta-refresh to the same requested host/uri  
    set ::html_response_string " 
  
  
 Hi there 
  
  
  
 Meta-refresh to http://\[HTTP::host\]\[HTTP::uri\] in $::refresh_interval seconds 
  
  
    " 
 } 
 when HTTP_REQUEST { 
  
    if {[HTTP::path] starts_with "/meta"}{ 
  
       log local0. "response string: [subst $::html_response_string]" 
       HTTP::respond 200 content [subst $::html_response_string] 
  
    } else { 
       HTTP::respond 200 content "\r\n200\tClient IP:port: [IP::client_addr]:[TCP::client_port]\ 
          -> VIP IP:port: [IP::local_addr]:[TCP::local_port]\r\n" 
    } 
 }

Aaron