balancer load balancer high availability reverse proxy

http://code.google.com/p/haproxy-docs/wiki/source

sudo aptitude update; sudo aptitude install haproxy

En este ejemplo:

| 10.0.0.15 | Balanceador de carga (haproxy) | |
| 10.0.0.4 | Servidor web 1 | Escucha en TCP 666 |
| 10.0.0.5 | Servidor web 2 | Escucha en TCP 666 |

sudo mv /etc/haproxy/haproxy.cfg /etc/haproxy/haproxy.cfg.old
sudo vim /etc/haproxy/haproxy.cfg

global
        log 127.0.0.1   local0
        log 127.0.0.1   local1 notice
        #log loghost    local0 info
        maxconn 4096
        #chroot /usr/share/haproxy
        user haproxy
        group haproxy
        daemon
        #debug
        #quiet

defaults
        log     global
        mode    http
        option  dontlognull
        retries 3
        option redispatch
        maxconn 2000
        contimeout      5000
        clitimeout      50000
        srvtimeout      50000

listen webfarm 10.0.0.15:80
        mode http
        balance roundrobin
        cookie SERVERID insert indirect
        option httpchk HEAD /index.html HTTP/1.0
        option  httplog
        server webA 10.0.0.4:80 cookie A check
        server webA 10.0.0.5:80 cookie B check


listen test 10.0.0.15:666
        mode tcp
        balance roundrobin
        server testA 10.0.0.4:666
        server testB 10.0.0.5:666

Ejemplo TCP (da un warning si mantenemos

sudo /etc/init.d/haproxy restart

Probar:

wget -O - http://10.0.0.15

http://kevin.vanzonneveld.net/techblog/article/haproxy_logging/

1. Crear una entrada en rsyslog para haproxy

sudo vim /etc/rsyslog.d/haproxy.conf

Con el siguiente contenido:

$ModLoad imudp
$UDPServerRun 514
$UDPServerAddress 127.0.0.1
 
# ..and in any case, put these two in /etc/rsyslog.d/haproxy.conf:
local1.* -/var/log/haproxy_1.log

& ~ 
# & ~ means not to put what matched in the above line anywhere else for the rest of the rules
# http://serverfault.com/questions/214312/how-to-keep-haproxy-log-messages-out-of-var-log-syslog

2. Reiniciar rsyslogd:

sudo /etc/init.d/rsyslog restart

3. Editar:

sudo vim /etc/haproxy/haproxy.conf

Y dejar la siguiente linea dentro de la seccion 'global':

global
        log             127.0.0.1       local1 debug

4. Reiniciar haproxy y ver el log:

sudo /etc/init.d/haproxy restart
sudo tail -F /var/log/haproxy_1.log

5. (Opcional) rotar logs:

/etc/logrotate.d/haproxy

/var/log/haproxy*.log
{
    rotate 4
    weekly
    missingok
    notifempty
    compress
    delaycompress
    sharedscripts
    postrotate
        reload rsyslog >/dev/null 2>&1 || true
    endscript
}