HAProxy : HTTP Load Balancing

HAProxy : HTTP Load Balancing 2015/02/18

Install HAProxy to configure Load Balancing Server. This example based on the environment like follows. | -------+----------------------------------------------- | +-------------------+--------------------+ |10.0.0.30 |10.0.0.31 |10.0.0.32 +-----+-----+ +-------+------+ +-------+------+ | Frontend | | Backend#1 | | Backend#2 | | HAProxy | | Web Server | | Web Server | +-----------+ +--------------+ +--------------+

	Configure Servers that HTTP connection to HAProxy Server is forwarded to backend Web Servers.
[1]	Install HAProxy.

[root@dlp ~]#  yum -y install haproxy

[2]	Configure HAProxy.

[root@dlp ~]#  mv /etc/haproxy/haproxy.cfg /etc/haproxy/haproxy.cfg.org  [root@dlp ~]#  vi /etc/haproxy/haproxy.cfg # create new global       # for logging section log 127.0.0.1 local2 info chroot /var/lib/haproxy pidfile /var/run/haproxy.pid       # max per-process number of connections maxconn 256       # process' user and group user haproxy group haproxy       # makes the process fork into background daemon defaults       # running mode mode http       # use global settings log global       # get HTTP request log option httplog       # timeout if backends do not reply timeout connect 10s       # timeout on client side timeout client 30s       # timeout on server side timeout server 30s # define frontend ( set any name for "http-in" section ) frontend http-in       # listen 80 bind *:80       # set default backend default_backend backend_servers       # send X-Forwarded-For header option forwardfor # define backend backend backend_servers       # balance with roundrobin balance roundrobin       # define backend servers server www01 10.0.0.31:80 check server www02 10.0.0.32:80 check [root@dlp ~]#  systemctl start haproxy  [root@dlp ~]#  systemctl enable haproxy

[3]	Configure Rsyslog to get logs for HAProxy.

[root@dlp ~]#  vi /etc/rsyslog.conf # line 15,16: uncomment, lne 17: add $ModLoad imudp $UDPServerRun 514 $AllowedSender UDP, 127.0.0.1 # line 54: change like follows *.info;mail.none;authpriv.none;cron.none ,local2.none    /var/log/messages local2.* /var/log/haproxy.log [root@dlp ~]#  systemctl restart rsyslog

[4]	Change httpd settings on Backends to logging X-Forwarded-For header.

[root@www ~]#  vi /etc/httpd/conf/httpd.conf # line 196: change like follows LogFormat " \"%{X-Forwarded-For}i\"  %l %u %t \"%r\" %>s %b \"%{Referer}i\" \"%{User-Agent}i\"" combined [root@www ~]#  systemctl restart httpd

[5]	Make sure all works fine to access to the frontend server from a Client with HTTP like follows.