Creating a BI Servers Cluster

After installing BI server, it is necessary to change the Settings.xml configuration file for each of them:

• In the Statable parameter set the Yes value.

• In the StateServer section specify state server parameters.

NOTE. Working with the state server is available if monikers are generated by the BI server via GUID, that is why make sure that the KeyIncr parameter is set to 0 in the configuration file.

Example:

<...>

  <Key Name="PP">

    <BIS>

      <Key Name="System">

        <...>

        <Session ... Statable="Yes" ... />

        <StateServer Host="StateServer" Port="11211" Type="MemCached" />

        <...>

      </Key>

    </BIS>

  </Key>

</...>

To use nginx balancer together with BI servers of Foresight Analytics Platform after installation edit the nginx.conf configuration file (located in the folder "...\nginx\conf\" on working in Windows or "/etc/nginx/ on working in Linux). The file must have the following contents:

worker_processes  1;

worker_rlimit_nofile 20240;

events {

    worker_connections  20240;

}

http {

    log_format upstream   '$upstream_addr - $upstream_status | $request - [ $upstream_response_time ]';

    upstream backend {

        sticky;

 

        server <BIServer1>;

        server <BIServer2>;

    }

    server {

        listen   555;

        server_name  <NginxServerName>;

        access_log      logs/nginx_upstream_access.log  upstream;

        location / {

            proxy_set_header X-Real-IP $remote_addr;

            proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;

            proxy_set_header Host $host:555;

            proxy_pass  http://backend;

        }

    }

}

• In the "server" directive, specify parameters of the virtual server, which the web application will address: in the "listen" directive, specify the port for working; in the "server_name" directive, specify the name of the server, at which nginx is running.

• In the "location" directive, specify query forwarding rules. In the "proxy_pass" directive, specify a section, which describes severs, at which it is necessary to set up forwarding.

• The "upstream" directive stores the list of servers, to which queries are forwarded. Specify the name, which will be used in the "location" directive, after the "upstream" keyword.

• The "sticky" directive specifies that all queries of one client are linked to and will be sent to one BI server selected according to configured balancing method. If the assigned server cannot handle a query, a new server is selected as if the client is not linked to the server. The information about the server, to which these or those queries must be sent, is transferred via HTTP cookies. To make this directive work in nginx, set up the "nginx-sticky" additional module (by default it is not included in the assembly).

• In the "server" directives, specify names or IP addresses of BI servers, to which the queries will be forwarded.

Example:

If the configuration file contains the following values:

    upstream backend {

        sticky;

 

        server BIServer1;

        server BIServer2;

    }

    server {

        listen   555;

        server_name  BIServer;

        access_log      logs/nginx_upstream_access.log  upstream;

        location / {

            proxy_set_header X-Real-IP $remote_addr;

            proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;

            proxy_set_header Host $host:555;

            proxy_pass  http://backend;

        }

    }

All queries received at http://BIServer:555/axis2/services/PP.SOM.Som will be forwarded to BI servers at http://BIServer1/axis2/services/PP.SOM.Som and http://BIServer2/axis2/services/PP.SOM.Som/.

For details about parameters specified in the nginx.conf configuration file see the documentation on nginx: http://nginx.org/en/.

To make the web application work via the nginx balancer, in the PP.xml file specify the path to the balancer instead of the BI server:

<?xml version="1.0" encoding="utf-8" ?>

<pp>

      <service url="http://BIServer:555/axis2/services/PP.SOM.Som" timeout="120000" />

      <metabase id="PPRepository" ping="120000" recentObjects="false" />

      <cultures>

            <culture cultureName="ru" />

            <culture cultureName="en" />

      </cultures>

      <...>

</pp>