[linux]how to install and config haproxy(load balance)

• get the haproxy rpm

• haproxy-1.4.22-3.el6.x86_64.rpm

• set the configure file

# vi /etc/haproxy/haproxy.cfg 

#---------------------------------------------------------------------
# main frontend which proxys to the backends
#---------------------------------------------------------------------

frontend  nameOfPort1*:18001
    acl url_static       path_beg       -i /static /images /javascript /stylesheets
    acl url_static       path_end       -i .jpg .gif .png .css .js

    use_backend static          if url_static
    default_backend            nameOfPort1

frontend  nameOfPort1*:18002
    acl url_static       path_beg       -i /static /images /javascript /stylesheets
    acl url_static       path_end       -i .jpg .gif .png .css .js

    use_backend static          if url_static
    default_backend            nameOfPort2

#---------------------------------------------------------------------
# round robin balancing between the various backends
#---------------------------------------------------------------------
backend nameOfPort1
    balance     roundrobin
    server  app1 123.456.789.123:25500 check
    server  app2 123.456.789.124:25500 check
    server  app3 123.456.789.125:25500 check

backend nameOfPort2
    balance     roundrobin
    server  app1 123.456.789.123:25501 check
    server  app2 123.456.789.123:25501 check
    server  app3 123.456.789.123:25501 check

• if you want to see log file, set the rsyslog

# vi /etc/rsyslog.conf

# Provides UDP syslog reception
$ModLoad imudp
$UDPServerAddress 127.0.0.1
$UDPServerRun 514
SYSLOGD_OPTIONS="-m 0 -r"

local2.*                                                /var/log/haproxy.log

• restart rsyslog and haproxy

# service rsyslog restart
# service haproxy restart