Wow. So helpful Ruckus.
You can do it via ssh to the AP acting as the master:
Welcome to Ruckus Unleashed Network Command Line Interface
ruckus> enable
ruckus# config
You have all rights in this mode.
ruckus(config)# system
ruckus(config-sys)# syslog
ruckus(config-sys-syslog)# server 10.1.1.1
...etc.
server Sets the syslog server address. facility Sets the syslog facility name (local0 - local7).priority Sets the syslog priority level (emerg, alert, crit, err, warning, notice, info, debug).ap-facility Sets the AP syslog facility name (local0 - local7).ap-priority Sets the AP syslog priority level (emerg, alert, crit, err, warning, notice, info, debug).and save it.