Web server won't allow more than 4 connections

问题

I am running WEB.API backend with Angular front end, using SignalR (2.2.0) with almost constant data changes.

My problem is that I am able to connect only 4 clients, 5th client would not connect. It will load all web page data, but SignalR won't connect. As soon as I disconnt one of the 4 already connected clients, the 5th one would connect with not problems.

This is running on Windows 8.1 with IIS 8.5 on separate LAN.

IIS settings is default. Where shall I start looking to solve this?

Thank you.

update: in addition to below link provide by @thab, here is another one with concurent connection limits in IIS per Windows version: http://jpelectron.com/sample/WWW%20and%20HTML/IIS-%20OS%20Version%20Limits.htm

回答1:

I think it's because you're using Windows 8.1 - there's a limit to the number of simultaneous connections that IIS supports on non-server versions of Windows:

http://weblogs.asp.net/owscott/windows-8-iis-8-concurrent-requests-limit

The problem relates to how SignalR holds a persistent connection (whether Forever Frames, Server Sent Events or Web Sockets) and if the limit is 10 connections, then you'll only be able to get a few users online at once...

来源：https://stackoverflow.com/questions/34854939/web-server-wont-allow-more-than-4-connections