Using wget to determine if ELB is misconfigured and is attached to a private subnet

Typically, you would want ELB's to be available in atleast 2 zones in a particular region, so that if one zone goes down, the ELB in the second zone will handle all the requests. If you ELB is configured correctly for multiple zones, you can do a "nslookup" on the ELB A record and you will get multiple EIP's returned (1 for each zone)

If the ELB is attached to a private subnet, you would see a request failure using wget:-

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$ wget http://<elb-name>.ap-northeast-1.elb.amazonaws.com/index.html
--2014-09-08 18:08:29--  http://<elb-name>.ap-northeast-1.elb.amazonaws.com/index.html
Resolving <elb-name>.ap-northeast-1.elb.amazonaws.com (<elb-name>.ap-northeast-1.elb.amazonaws.com)... 54.92.98.228, 54.238.149.12
Connecting to <elb-name>.ap-northeast-1.elb.amazonaws.com (<elb-name>.ap-northeast-1.elb.amazonaws.com)|54.92.98.228|:80... failed: Connection timed out.
Connecting to <elb-name>.ap-northeast-1.elb.amazonaws.com (<elb-name>.ap-northeast-1.elb.amazonaws.com)|54.238.149.12|:80... connected.
HTTP request sent, awaiting response... 200 OK
Length: unspecified [text/xml]
Saving to: `index.html'
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The other way to confirm and check is through the AWS console:-

In the consile make sure the "subnet id" in the ELB's availability zone's have an igw-* associated with the zones that it has been added to. ELB's need to be public subnets so that they can be accessed from outside.