Proxying Meteor WebSockets through IIS ARR

Question

We have a need to proxy Meteor through an IIS proxy. An IIS site accepts bindings for a particular Meteor website and proxies the requests through to an alternate port.

Web sockets are not working and Meteor is reverting to XHR.

Web.Config file as follows:

<rule name="Meteor reverse proxy" stopProcessing="true">
    <match url="(.*)" />
    <conditions>
        <add input="{CACHE_URL}" pattern="^(.+)://" />
    </conditions>
    <action type="Rewrite" url="{C:1}://127.0.0.1:8008/{R:1}" />
</rule>

By accessing the website via 127.0.0.1:8008 on the server it works fine. Accessing the website through the IIS proxy fails.

I have noticed IIS ARR is changing the casing of the headers, removing a header (sec-websocket-extensions) and adding a handful of extras. This might not be related.

IIS Proxy:

Direct:

MS documentation recommends disabling WebSockets when in use alongside NodeJS. Updating this setting does not help. http://www.iis.net/learn/get-started/whats-new-in-iis-8/iis-80-websocket-protocol-support#TOC301258519

Has anyone come across this issue?

Update You'll notice the header above references ARR2.5, this version does not support web sockets. 3.0 is required to proxy sockets.

Answer 1

After testing the proxy via an alternative web socket hello world, ARR was proxying web sockets successfully. To solve the issue we disabled compression on web sockets within Meteor.

SERVER_WEBSOCKET_COMPRESSION environment variable to 0

https://forums.meteor.com/t/websocket-compression-introduced-in-meteor-1-2-doesnt-work-with-passenger-docker-nginx/12025