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    <p>Hey guys, i have discovered the process registry for nitrogen called: <i><b>nprocreg</b></i>. <br> When you check your apps folder ( <i>$NITROGEN_INSTALL_DIR/apps/nprocreg </i>).</p> <p> In this application, processes can be spawn across more than one nitrogen app servers even across multiple machines. To experiment with this, start 2 erlang nodes on two differnt hosts. ping them so that they are connected. (<code>net_adm:ping(?OTHER_NODE)</code>). Now, start nitrogen on both erlang nodes. You could actually first start the nitrogen and then ping the two nodes <br> Make sure that the two nitrogen nodes are using long names i.e [NAME]@IP_ADDRESS on a LAN. <br><br> Now, on a third machine on your LAN, create a DNS (Name Server) . Put the same name mapping onto two different IP Adresses of our two nodes running the nitrogen applications. Configure the two computers runnind nitrogen to ensure that they point to the DNS IP address for DNS Services (Actually do this for all the computers in your LAN). <br> You will discover that when you request for a page (residing in the doc root of both nitrogen apps) from several computers on your LAN, using the mapped name in your browser you see that the DNS server does some kind of Load balancing. <br> Now, Ensure that the page you are requesting for can show you from which nitrogen server its coming from on the interface. This page must have say a button which generates an event that will <code>wf:flash(wf:f("Some statement on the interface",[]))</code><br> Now, request this page on two different computers and note where each is being served from. Next, go to one nitrogen server and stop it. <br> When you now click on the button on the browser which got its page the nitrogen server that we have just put down, it still works. <br> This is why, Rusty and the friends discovered that if nitrogen processes can be registered across more nitrogen apps, when run behind a load balancer, the events can be fowarded to any nitrogen app in the cluster. <br> Of course this works well if you ensure that the two apps on different machines have the same pages, modules and configuration of paths. This is because the event call back function maybe calling say a database API. <br> An example of load balancing using DNS Server can be seen when you 'dig' google from your terminal on linux or solaris like this: <pre> dig www.google.com </pre> You will see that the name server has the same name mapped onto several Ip adresses. This ensures availability across domains and ensures some kind of load balancing <br> /joshmuza@gmail.com </p>
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    1. POAre events always run in the same process in Nitrogen?
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    1. USMuzaaya Joshua
    1. USMuzaaya Joshua
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