Nginx and PHP using a consistent hashing algorithm for memcached cluster and load balancing

First, you need to compile a third party module (ngx_http_consistent_hash) for Nginx 1. Download Ngx_http_consistent_hash-master, unzip
2. View installed Nginx compilation parameters:/usr/local/nginx/sbin/nginx-v
3. Nginx Decompression directory to perform:./configure--prefix=/usr/local/nginx--add_module=/usr/local/src/ngx_http_consistent_ hash-master/
(/usr/local/nginx: Original nginx compiled path, usr/local/src/ngx_http_consistent_hash-master/: Third party module directory path)
4. Because compiled Nginx may be running: pkill-9 nginx
5. Make && make install


II. Configuration of Memcache cluster
1. Use the memcached node and declare it in a group
Upstream Memserver {
Hash_key $request _uri; #hash计算时的依据, based on the URI to hash
Server localhost:11211;
Server localhost:11212;
Server localhost:11213;
}
2.location in
Location/{
Set $memcached _key $uri;
Memcached_pass Memserver; #memserver为上面的memcache节点的名称
Error_page 404/writemem.php;
}


3. Restart Nginx:./sbin/nginx-s Reload


4. Open the 3 memcache servers:
/usr/local/memcached/bin/memcached-u nobody-vv-p 11211
/usr/local/memcached/bin/memcached-u nobody-vv-p 11212
/usr/local/memcached/bin/memcached-u nobody-vv-p 11213




5.
The above is the default load balancing algorithm: Set the counter, turn to request N servers.
We want to use the installed third party module: (Top installed)
such as Http://wiki.nginx.org/NginxHttpUpstreamConsistentHash
This module is to use a consistent hash to request the backend node, and its algorithm, in PHP with the Memcache module of the consistent hash algorithm, compatible.
After the module is installed, in nginx.conf:
Upstream Memserver {
Consistent_hash $request _uri;
Server 127.0.0.1:11211;
Server 127.0.0.1:11212;
Server 127.0.0.1:11213;
}


6. In php.ini, the following configuration: Memcache.hash_strategy = consistent
In this way: Nginx and PHP can complete the memcached cluster and load balancing algorithm.


Kill PHP Process: pkill-9 php-fpm
Start PHP:/USR/LOCAL/PHP/SBIN/PHP-FPM


7.writemem.php Write Memcache operations:
<?php
$uri = $_server[' Request_uri ']; Key to receive user queries


PHP also wants to add as many servers as Nginx
$mem = new Memcache ();
$mem->addserver (' 127.0.0.1 ', 11211);
$mem->addserver (' 127.0.0.1 ', 11212);
$mem->addserver (' 127.0.0.1 ', 11213);


Querying the database
Todo...


Write to Memcached
$mem->add ($url, ' value ', 0,300);
$mem->close ();
?>