HAProxy Load Balancing - Revision history

Brian: /* HAProxy Load Balancing */

2019-06-25T16:03:40Z

‎HAProxy Load Balancing

Brian: /* HAProxy Troubleshooting */

2019-06-25T15:50:46Z

‎HAProxy Troubleshooting

Brian: /* Configuring HAProxy for Load Balancing Layer 7 */

2019-06-25T15:46:26Z

‎Configuring HAProxy for Load Balancing Layer 7

Brian: /* HAProxy Load Balancing */

2019-06-25T15:44:25Z

‎HAProxy Load Balancing

Brian: /* Let's Configure the Firewall for traffic and stats port */

2019-06-25T15:43:03Z

‎Let's Configure the Firewall for traffic and stats port

Brian at 15:41, 25 June 2019

2019-06-25T15:41:37Z

Brian: Created page with "==HAProxy Load Balancing=="

2019-06-19T07:26:47Z

Created page with "==HAProxy Load Balancing=="

New page

==HAProxy Load Balancing==

@@ Line 9: / Line 9: @@
 # Web02
 # Database Server (However not shown in this configuration)
 ===HAProxy 1.7 on CentOS Install===

← Older revision		Revision as of 15:50, 25 June 2019
Line 105:		Line 105:

	We ran into a few issues at first with spellings, with this configuration everything is dumped into /var/log/messages		We ran into a few issues at first with spellings, with this configuration everything is dumped into /var/log/messages
		+
		+	===High Availability===
		+	The layer 4 and 7 load balancing setups described before both use a load balancer to direct traffic to one of many backend servers. However, your load balancer is a single point of failure in these setups; if it goes down or gets overwhelmed with requests, it can cause high latency or downtime for your service.
		+
		+	A high availability (HA) setup is an infrastructure without a single point of failure. It prevents a single server failure from being a downtime event by adding redundancy to every layer of your architecture. A load balancer facilitates redundancy for the backend layer (web/app servers), but for a true high availability setup, you need to have redundant load balancers as well.

@@ Line 98: / Line 98: @@
 The additional stats URI /haproxy?stats enables the statistics page at that specified address.
-After making the configurations, save the file and restart HAProxy with the next command.
+After making the configurations, save the file and restart [[Main_Page#HAProxy|HAProxy]] with the next command.
   systemctl restart haproxy

@@ Line 1: / Line 1: @@
 ==HAProxy Load Balancing==
-Are you looking for a solution for load balancing your website across multiple nodes?  This is installed on a CentOS 7 Cloud nodes, so we can easily add additional webnodes if/when required.
+Are you looking for a solution for load balancing your website across multiple nodes?  Here is an example using [http://www.haproxy.org/ HAProxy] on CentOS 7 Cloud nodes, so we can easily add additional webnodes if/when required.
 For this example I will be using a 4 cloud servers, haproxy/web01/web02/database server

@@ Line 54: / Line 54: @@
   firewall-cmd --permanent --zone=public --add-service=http
   firewall-cmd --permanent --zone=public --add-service=https
   firewall-cmd --reload

← Older revision		Revision as of 15:41, 25 June 2019
Line 1:		Line 1:
	==HAProxy Load Balancing==		==HAProxy Load Balancing==
		+
		+	Are you looking for a solution for load balancing your website across multiple nodes? This is installed on a CentOS 7 Cloud nodes, so we can easily add additional webnodes if/when required.
		+
		+	For this example I will be using a 4 cloud servers, haproxy/web01/web02/database server
		+
		+	# Haproxy Server
		+	# Web01
		+	# Web02
		+	# Database Server (However not shown in this configuration)
		+
		+	===HAProxy 1.7 on CentOS Install===
		+
		+	I will not be installing anything besides haproxy on this node, to reduce resource consumption.
		+
		+	yum install gcc pcre-static pcre-devel openssl-devel htop vim openssl mod_ssl -y
		+
		+	Now lets install HAProxy 1.7 from source
		+
		+	wget https://www.haproxy.org/download/1.7/src/haproxy-1.7.9.tar.gz
		+	tar xzvf haproxy-1.7.9.tar.gz
		+	cd haproxy-1.7.9
		+
		+	The next command has added support for openssl, as later this will be used for https connections and I recommended setting this up now, so it's there when needed.
		+
		+	make TARGET=linux2628 USE_PCRE=1 USE_OPENSSL=1 USE_ZLIB=1 USE_CRYPT_H=1 USE_LIBCRYPT=1
		+	make install
		+
		+	Create a few needed directories and files
		+
		+	mkdir -p /etc/haproxy
		+	mkdir -p /var/lib/haproxy
		+	touch /var/lib/haproxy/stats
		+
		+	Create a symbolic link for the binary to allow you to run HAProxy commands as a normal user.
		+
		+	ln -s /usr/local/sbin/haproxy /usr/sbin/haproxy
		+
		+	If you want to add the proxy as a service to the system, copy the haproxy.init file from the examples to your /etc/init.d directory. Change the file permissions to make the script executable and then reload the systemd daemon.
		+
		+	cp ./example/haproxy.init /etc/init.d/haproxy
		+	chmod 755 /etc/init.d/haproxy
		+
		+	Now we need to reload the damon and make sure HAProxy starts if the server ever gets rebooted
		+
		+	systemctl daemon-reload
		+	chkconfig haproxy on
		+	useradd -r haproxy
		+
		+	That went pretty easy and fast, now comes the fun part of configuring the server
		+
		+	===Let's Configure the Firewall for traffic and stats port===
		+
		+	firewall-cmd --permanent --zone=public --add-service=http
		+	firewall-cmd --permanent --zone=public --add-service=https
		+	firewall-cmd --permanent --zone=public --add-port=1936/tcp
		+	firewall-cmd --reload
		+
		+	Setting up HAProxy for load balancing is a quite straight forward process. Basically, all you need to do is tell HAProxy what kind of connections it should be listening for and where the connections should be relayed to.
		+	This is done by creating a configuration file /etc/haproxy/haproxy.cfg with the defining settings. You can read about the configuration options at HAProxy documentation page if you wish to find out more.
		+
		+	===Configuring HAProxy for Load Balancing Layer 7===
		+
		+	vi /etc/haproxy/haproxy.cfg
		+
		+	Add the following for a basic configuration, which will get everything up and running without https/port 443 support.
		+
		+	global
		+	log /dev/log local0
		+	log /dev/log local1 notice
		+	chroot /var/lib/haproxy
		+	stats timeout 30s
		+	user haproxy
		+	group haproxy
		+	daemon
		+
		+	defaults
		+	log global
		+	mode http
		+	option httplog
		+	option forwardfor
		+	option dontlognull
		+	timeout connect 5000
		+	timeout client 50000
		+	timeout server 50000
		+
		+	frontend http_front
		+	bind *:80
		+	stats uri /haproxy?stats
		+	default_backend http_back
		+
		+	backend http_back
		+	balance roundrobin
		+	server web01 255.255.255.1:80 check
		+	server web02 255.255.255.2:80 check
		+
		+	This defines a layer 4 load balancer with a front-end name http_front listening to the port number 80, which then directs the traffic to the default backend named http_back.
		+
		+	The additional stats URI /haproxy?stats enables the statistics page at that specified address.
		+
		+	After making the configurations, save the file and restart HAProxy with the next command.
		+
		+	systemctl restart haproxy
		+
		+	===HAProxy Troubleshooting===
		+
		+	We ran into a few issues at first with spellings, with this configuration everything is dumped into /var/log/messages