option a: install a nagios core server in the remote environment and have it send alert data to the mothership nagiosxi running in the clouds. install the ncpa agent on the now local vanilla syslog server. use active or passive checks to feed delicious alert data to the nagios core server which then feeds the (still) delicious alert data to the mothership nagiosxi running in the clouds.
option b: only install the ncpa agent on the remote vanilla office syslog server; have it perform passive checks that are relayed to the mothership nagiosxi running in the clouds.
a) is option a even technically possible (e.g. connecting a nagios core server to a nagiosxi server)? b) what are the conditions that would make option a preferable? option b is a lot less work but #askTheGeniuses