When upgrading a WAAE instance, in some occasion it is impossible to set the "Security Server Name". Pressing Next would request the server name to be entered and the installation is stuck.
To be able to run the installation, set AS_EEM_CHECK_INFO to your EEM server, then re-run the installation.
# AS_EEM_CHECK_INFO=<EEM Server Name>
# export AS_EEM_CHECK_INFO
# ./wa_setup.sh