Configuring Load-Balanced Clusters - Testing the System continued
(Page 3 of 4 )

We’ll also check the system logs on lb:

  # tail /var/log/syslog
  Sep 11 22:59:45 mail ldirectord[8543]: Added virtual server:
  70.253.158.44:80
  Sep 11 22:59:45 mail ldirectord[8543]: Added fallback server: 127.0.0.1:80
  ( x 70.253.158.44:80) (Weight set to 1)
  Sep 11 22:59:45 mail ldirectord[8543]: Added real server: 70.253.158.41:80
  ( x 70.253.158.44:80) (Weight set to 1)
  Sep 11 22:59:45 mail ldirectord[8543]: Deleted fallback server: 127.0.0.1:80
  ( x 70.253.158.44:80)
  Sep 11 22:59:46 mail ldirectord[8543]: Added real server: 70.253.158.45:80
  ( x 70.253.158.44:80) (Weight set to 1)

Back on web1 and web2, check the Apache access logs. The director should demand director.html everycheckintervalseconds:

  70.253.158.44 - - [11/Sep/2006:22:49:37 -0500] "GET /director.html HTTP/1.1"
  200 11 "-" "libwww-perl/5.803"
  70.253.158.44 - - [11/Sep/2006:22:49:39 -0500] "GET /director.html HTTP/1.1"
  200 11 "-" "libwww-perl/5.803"

In your browser, go to the virtual site URL http://70.253.158.42/which.html, and you should see either:

  I'm web1

or:

  I'm web2

If the load balancer is broken or one of the web servers is down, you might always get a response from the same web server.

Now, stop Apache on web1:

  # /etc/init.d/apache stop

Reload/refresh your browser page to access http://70.253.158.42/which.html again. You should always get the response:

  I'm web2

Next: Adding HA to LB >>
 

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