I have already had a working Master - Slave Configuration on my Jenkins, but an update broke it so I had to reinstall it (didn't have a backup yet).
But now after reinstalling Jenkins I don't get it to work anymore.
When I go on Manage Jenkins -> Node Management I can only add new "permanent" Agents and not the old "Dumb Slave" Node I used to have. Was there an update or something so this doesn't work anymore?
Also when using this permanent Agent the help ? shows me the option "Launch agent via Java Web Start" on the Launch method field - but in the drop down it is not available.
Did I make something wrong on the installation?
edit: Using newest Version 2.16 of Jenkins
Ok, I found it myself!
In the Global Security, I didn't have a TCP port for JNLP agents enabled, which automatically disables the line "Launch agent via Java Web Start"
As mentioned here:
Manage Jenkins => Configure Global Security => Enable security => TCP port for JNLP agents Set it to either Fixed (for this option also set the port number) or Random.