0

Why can't my internal IP addresses be granted access from IIS 10 IP Address and Domain Restrictions?

Backstory:

I have implemented IIS 10's IP Address and Domain Restrictions to block access to one particular website for all but an authorized set of IP addresses. I have had several internal IP address and subnets included in that set for several weeks. Yesterday I made a change to my set/list to add a couple more customer IP addresses. I also changed my 10.10.1.x IP addresses to a single 10.10.1.0 subnet address. This morning I got a text from my boss asking why a coworker was getting a 403 Forbidden response when he tried to access the site in question. He was on the local network and I had a 192.168.1.0 subnet address in place that should have granted him access. I tried removing and re-adding the subnet address. I tried using an IP address range (192.168.1.1 - 192.168.1.254). I even tried our external public IP address. Nothing has worked yet. What strange is that all the other IP addresses seem to be working. I am working from home so I used my public IP address to test.

So, all that being said, do you have any ideas what might be going on? It seems like this is only affecting internal network addresses.

jlavallet
  • 101
  • 3
  • Who is the network administrator of your team? Let him/her tell how that coworker's browser connects to this IIS machine, and which IP address is being seen by IIS. Obviously it won't be `192.168.1.x`. – Lex Li Mar 03 '21 at 17:10

1 Answers1

0

Well, I can't explain it but after I got a little outside consulting, the solution was to enter the 192.168.1.0 subnet address and then a 255.255.255.0 subnet mask. It makes sense but what does not make sense is why my original set up was working up until today.

Him will

jlavallet
  • 101
  • 3