It seems as if it may be related to Undertow/RunWar? When we use Lucee standalone (i.e., no CommandBox) and/or with Tomcat, the Websockets extension works fine.
I don’t know anything about the extension, nor have I tried it, but can you post your web.xml overrides so I can see them? Also, we didn’t write that websocket project nor do we support it. I’d recommend finding the ticket tracker for that project to ask on as well.
Thanks. We looked at socket.io-lucee originally but it said it was “alpha” and didn’t support the latest version of socket.io, so we decided not to explore it further. I guess we’ll have to just install Lucee as standalone instead of via CommandBox for our clients, which is a same since its so useful.
Will get the web.xml from our developer and post here.