load balancing

Question

Dear all,

What is the function of Web Adaptor ? Is it just to redirect request ?

Suppose I have 3 arcgis server machines configured as 1 cluster. Do I need Web Adaptor ? Isnt the work load between servers already spread out automatically since I have all of them in 1 cluster ?

What I mean is... say there is a request to a map service. The request can go straight away to the arcgis server address (I disregard the security, this is just a mere load balance test) instead of going to Web Adaptor first... The load balancing will be automatic. Right ?

Correct me if my understanding is wrong

Thanks

HaniuHokkaido · Answer

Thanks Derek. Thanks Ciava

DerekLaw · Answer

Hi Haniu, What is the function of Web Adaptor? Is it just to redirect request?

The Web Adaptor enables you to leverage a 3rd party web server (e.g., IIS) as part of your GIS site. Domenico already referenced the help topic that describes its benefits; and one of the key ones is it helps make your site more secure. Suppose I have 3 arcgis server machines configured as 1 cluster. Do I need Web Adaptor? Isnt the work load between servers already spread out automatically since I have all of them in 1 cluster?

No, in this scenario the Web Adaptor is not required, but strongly recommended. And yes, the work load is spread between the 3 GIS Servers when they are in the same cluster.

Hope this helps,

nicogis · Answer

see about web adaptor http://resources.arcgis.com/en/help/main/10.1/0154/01540000028p000000.htm

"...The Web Adaptor detects the GIS servers that participate in the site and forwards requests to each in a round-robin fashion. The GIS servers also perform some degree of request distribution among themselves.

Some server operations, such as batch geocoding, are very CPU intensive. Using clustered servers for this type of operation may help free up other machines in your site so that your remaining services can remain online unencumbered..."

see Deployment scenarios http://resources.arcgis.com/en/help/main/10.1/0154/015400000488000000.htm