How to redirect a client to a second server

[clarissa1996]

Hi,

I have a webpage installed on two different servers.
To improve system availability, if the first server is not available the client must be redirected to the second server.

To this purpose I have the following javascript installed on a third (high-available server).
The trick is to test if the file image.gif exists on the first server. If it's not possible to download this file, after 10 seconds the client is redirected to the second server.

This script works ok, but it seems that on certain clients it doesn't works (the client is always redirected to the second server).
I cannot debug this situation because I have no access to the client.

My question is:
is there a secure javascript to do this job ?

Thanks. Clarissa

------------------------------------------------------------

function host1() {
location.href = "

http://111.111.111.111/index.html";

}

function host2() {
location.href = "

http://222.222.222.222/index.html";

}

window.setTimeout("func2()", 10000);

document.write('Wait ...');
document.write('<img src="

http://111.111.111.111/image.gif"

onLoad="func1()"');
</script>

 

[BabyJeffy]

I wonder if there isn't a smarter way to do this that doesn't require the user has javascript enabled (nor does it require all users to wait for an image to download before they can progress).

Surely you could create a server-side solution that handed off the connections transparently.

Cheers,
Jeff

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[/tt]

What is Javascript? faq216-6094

 

[BillyRayPreachersSon]

Jeff is right - of all the methods you can use for load-balancing, client-side JavaScript is probably the least best you could have chosen.

Dan


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[/tt]

 

[clarissa1996]

Hi Jeff, hi Dan,

thanks for the quick reply.
here is some more informations.

> it require all users to wait for an image to download before they can progress
The file image.gif is 1 pixel ...

> methods you can use for load-balancing
My problem is not load-balancing, is high-availability.

> the user has javascript enabled
My application (homepage) require javascript enabled too.

> you could create a server-side solution that handed off the connections transparently
I cannot install cgi-script on the third server.


Regards. Clarissa

 

[BillyRayPreachersSon]

There are many other server-side technologies other than cgi. Does your server support anything else (ASP, PHP, JSP, CFM, etc etc etc etc?)



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[/tt]

 

[clarissa1996]

Thanks,

I will verify.


Regards. Clarissa