As the text in Teiid Instance administration indicates, you can change the admin port in the jboss management configuration, i. e. on the Overview tab of the Server Editor.
In order to do that, your server needs to be configured to use Management Operations instead of Filesystem and shell operations. You can then change the Management port in the Server Ports section. Don't forget to set the correct admin username and password (as that is not required when using filesystem operations).
EDIT: depending on your setup, you might need to define your server as remote. See this post for instructions: Re: Remote connection to teiid server from designer
thx. I can now connect to the management service. On the server view there is a window "Teiid instance", where a message says "no Teiid instance available on this JBoss server". How can I create a Teiid instance for this remote server? Earlier I used a local JBoss server and the instance was created as I previewed data (when I correctly remember). I now have both servers in my Designer and the local one is set as the default.
You would have to install Teiid runtime in the JBoss EAP before starting the JBoss Server to find the Teiid instance. Depending upon how you installed, you may need to start the JBoss Server with configuration file "standalone-teiid.xml" file. If this server is local, then you can configure your Designer's new server to use the configuration file "standalone-teiid.xml" file or, if it is remote you would need to start on console as
./standalone.sh -c standalone-teiid.xml
Then connect using the Designer, and configure as the remote server.