Shulou(Shulou.com)05/31 Report--

This article mainly shows you "how to use HAProxy", the content is easy to understand, clear, hope to help you solve your doubts, the following let the editor lead you to study and learn "how to use HAProxy" this article.

1. Installation:

# tar zcvf haproxy-1.3.20.tar.gz # cd haproxy-1.3.20

# make TARGET=linux26 PREFIX=/usr/local/haproxy # installing haproxy to / usr/local/haproxy,TARGET indicates the linux kernel version, which can be adjusted according to your own machine

# make install PREFIX=/usr/local/haproxy

2. Start:

Configuration files are required when HAProxy starts. For the first contact, you can start using the default configuration file haproxy.cfg in examples in the installation folder. For clarity, create a configuration file directory first.

# mkdir / usr/local/haproxy/conf

Copy the haproxy.cfg from the installation directory to / usr/local/haproxy/conf

Start the service: / usr/local/haproxy/sbin/haproxy-f / usr/local/haproxy/conf/haproxy.cfg

If you encounter the following error during startup:

"Cannot create * * directory / file"

Solution: mkdir directory

3. Configuration:

The configuration file is divided into two main parts: the global area and the agent area.

Global: mainly related to process parameters. As follows:

Log 127.0.0.1 local0 # log 127.0.0.1 local1 notice

# log loghost local0 info

Maxconn 4096

Chroot / home/develop/haproxy

Uid 99

Gid 504 # develop group id

Daemon

Nbproc 1

Pidfile / home/develop/haproxy/logs/haproxy.pid

Please refer to the official website for the meaning of other parameters and specific parameters.

Agency area: divided into three parts: defaults, listen, frontend, backend

Defaults: default parameters are set for the zones declared below (such as listen, frontend, backend). If another defaults is declared under a defaults, then the same parameter takes the value of the lowest defaults. As follows:

Mode http # working mode http agent, that is, layer 7. Other values: tcp (working in layer 4) / health

Option httplog

Option httpclose

Option dontlognull

Option forwardfor

Option redispatch

Retries 2

Maxconn 2000

Balance roundrobin # back-end server load balancing mode

Stats uri / haproxy-stats

Contimeout 5000

Clitimeout 50000

Srvtimeout 50000

Frontend: describes a series of sockets used to receive client-side links, equivalent to listen, bind, and accept functions in socket programming. As follows:

Bind 192.168.198.79 mode tcp 7910 # haproxy bind address and listening port mode tcp

Acl shunt src 10.28.169.231

Use_backend new_server if shunt

Default_backend old_server

Backend: describes the real server. Multiple servers can be defined in a configuration file. As follows:

Server second 192.168.198.77GRV 7910 # Real backend server

Server third 192.168.198.78:7910

A combination of listen:frontend and backend, usually used in tcp forwarding.

Powerful acl:

The syntax of acl is as follows:

Acl [flags] [operator]...

As follows:

Mode tcp

Acl shunt src 10.28.169.231

The name of this acl is shunt,criterion, src,value is 10.28.169.231. There are no flags and operator parts in this acl.

This means that if the ip address of the client requesting the link is 10.28.169.231, it matches. At first glance, the effect is not very great, but it can form a conditional judgment. For example, such an application scenario: if the request client address is 10.28.169.231, it is forwarded to the 10.28.169.114 server for execution, and the other request clients are forwarded to 10.28.169.12 for execution. You can meet the requirements according to the following configuration items:

Frontend only1

Bind 192.168.198.79:7910

Mode tcp

Acl shunt src 10.28.169.231

Use_backend new_server if shunt

Default_backend old_server

Backend new_server

Server first 10.28.169.114:7910

Backend old_server

Server second 10.28.169.12:7910

The above is all the contents of the article "how to use HAProxy". Thank you for reading! I believe we all have a certain understanding, hope to share the content to help you, if you want to learn more knowledge, welcome to follow the industry information channel!

Welcome to subscribe "Shulou Technology Information " to get latest news, interesting things and hot topics in the IT industry, and controls the hottest and latest Internet news, technology news and IT industry trends.