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Basically i owns 3 systems where one act as a Balancer Node , and the data for the websites resides over the other two.the balancer node balances the traffic among this 2 systems

Balancer System : Win Server 2008 ,WAMP,Proxy_balancer
Two Nodes : Light Weight Linux + Apache

Note :i dnt like NT Load Balancer
Node The Balancing is working well

The Problem is :

i want to update all the 2 nodes with the same data (means .php files , which my website is designed) when i update either one of them . note: .php source files have to be updated

Doubt :

i have also one doubt to ask can i basically call this system as a cloud ?

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up vote 1 down vote accepted

Some options from easiest to hardest (in my opinion)

There are a few ways to update the 2 sites. By far the easiest way would be to update them using a procedure which "does the same operation" on each node, for example executing the commands locally and across an SSH connection, or using subversion and checking the code out to both nodes, or maybe just setting up the first one and doing an rsync.

Setting up NFS - one server would be the NFS server, the second a client. This may negate the purpose of having a load balancer if the system is IO bound or the purpose of balancing is for fault tolerance (what happens if the box running the NFS server dies ?)

An alternative would be to run DRBD in dual primary mode (not trivial, but thats what its designed to do), which will mirror the block interface - ie a kind of network raid, where each half of the raid is available as the primary disk to 1 server, replicating to the other. (You will need to additionally run a filesystem which supports writes to 2 locations, from memory GFS2 does this)

There are various systems which can be set up, I assume, to look for filesystem changes - if you can hook them up to a script you can automate replication on change. I've never attempted this, but Lsyncd might be an option here (actually this might not be to hard, look at

The "Cloud" has no real meaning - yes, you can call this system a cloud. (I believe that the term Cloud originates from techos drawing the Internet as a cloud in technical diagrams, and this was co-opted by marketing people - basically anything "on the Internet" can be called "in the cloud" - The closest I have ascertained to finding a meaning for the term is "stuff stored where the end users don't need to worry about it" - Certainly at least 1 company I provide services to see themselves as a "cloud services provider", and is doing something not a lot different to what you are talking about.

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no way to upvote so thanks, hopes one day i will get 15 reputation for voting you – 7-isnotbad Mar 1 '13 at 10:41
+1 @davidgo Now got that reputation! – 7-isnotbad Sep 20 '13 at 13:38

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