mod_heartbeat - Apache HTTP Server Version 2.4









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Apache HTTP Server Version 2.4



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Apache Module mod_heartbeat

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Description:Sends messages with server status to frontend proxy
Status:Experimental
Module Identifier:heartbeat_module
Source File:mod_heartbeat
Compatibility:Available in Apache 2.3 and later
Summary

 mod_heartbeat sends multicast messages to a mod_heartmonitor listener 
that advertises the servers current connection count.  Usually, mod_heartmonitor
will be running on a proxy server with mod_lbmethod_heartbeat loaded, which allows
ProxyPass to use the "heartbeat" lbmethod inside
of ProxyPass.

    mod_heartbeat itself is loaded on the origin server(s) that serve requests 
    through the proxy server(s).  


    
        To use mod_heartbeat,
        mod_status and mod_watchdog
        must be either a static modules or, if a dynamic module, must
        be loaded before mod_heartbeat.
    


Topics

 Consuming mod_heartbeat Output
Directives

 HeartbeatAddress

Bugfix checklisthttpd changelogKnown issuesReport a bugSee also

Comments


Consuming mod_heartbeat Output
    
  
      Every 1 second, this module generates a single multicast UDP
      packet, containing the number of busy and idle workers.  The
      packet is a simple ASCII format, similar to GET query parameters
      in HTTP.
  
  
An Example Packet
v=1&ready=75&busy=0


  
    Consumers should handle new variables besides busy and ready,
    separated by '&', being added in the future.
  



HeartbeatAddress Directive

Description:Multicast address for heartbeat packets
Syntax:HeartbeatAddress addr:port
Default:disabled
Context:server config
Status:Experimental
Module:mod_heartbeat

The HeartbeatAddress directive specifies the
multicast address to which mod_heartbeat will send
status information. This address will usually correspond to a configured
 HeartbeatListen on a
frontend proxy system.
HeartbeatAddress 239.0.0.1:27999
    




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