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Can't run easy jss on linux post and replies

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Which port needs to be open?
Niels Walet
4 Posts

I get the following error on start up  (on my home computer)
java -jar EjsConsole.jar
Ok PreRegistry
java.rmi.ConnectException: Connection refused to host:; nested exception is:
java.net.ConnectException: Connection refused
No big surprise, since I have selinux turned on. The java version of EJS tuns fine, but I have issues with the javascript version. So what ports have to be open? Is it just 2008?

Replies to Which port needs to be open?

Re: Which port needs to be open? -
Francisco Esquembre
228 Posts

Hi Niels,

In principle, only port 2008 needs to be open, yes. This is used by Ejs to use a single EjsConsole when opening several sessions at the same time.

It surprises me that the Java version works fine but the JS one has problems. The JS launches either  a WebBrowser emulator or the default browser in the computer when running a model. So, maybe this communication fails if your security is very strict. Is this the problem?


Re: Re: Which port needs to be open? -
Niels Walet
4 Posts

Maybe the issue--the javascript version seems to start a java based web emulator, but that doesn't seem to work--i.e., doesn't seem to respond. Tried the generated web files, and see some effects.

I am still getting these annoying error messages, even though the console is happy. It might be that rmi connects to its default port as well? Is there an easy way to override some of the settings?

Sorry to be a pain, but the documentation of ejss seems to lag a little behind the functionality. I really would like to convert some of my java simulations ti javascript, especially with all the signing issues these days.


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