diff --git a/README.md b/README.md
index 20f613c..b6364b5 100644
--- a/README.md
+++ b/README.md
@@ -44,7 +44,7 @@ NRPE allows monitoring tools like NAGIOS or ICINGA to connect to clients for mon
 - manage selinux rule exceptions (optional)
 - manage NRPE service
 
-> Note: The value for the `nagios_server` variable is derived from a global parameter set in Foreman (`nagios_server`), because the paremeter is used across multiple modules. You need to set that manually in Foreman under "Global Parameters". Same for `nagios_source`, the value for the firewall source.
+> Note: The value for the `nagios_server` variable is derived from a global parameter set in Foreman (`nagios_server`), because the paremeter is used across multiple modules. You need to set that manually in Foreman under "Global Parameters". Same for `nagios_source`, the value for the firewall source, which should point to the source IP or source range for the nagios server querying NRPE.
 
 ## Repo Documentation