diff --git a/tmp/postinstall b/tmp/postinstall
index b03f415..59b01ca 100644
--- a/tmp/postinstall
+++ b/tmp/postinstall
@@ -1,4 +1,9 @@
 #!/bin/bash
 
-groupadd -g 65534 nobody >/dev/null 2>/dev/null
+if [ ! getent passwd nagios 2>&1 >/dev/null ]; then
+	useradd -u 52 nagios >/dev/null 2>/dev/null
+fi
+if [ ! getent group nobody 2>&1 >/dev/null ]; then
+	groupadd -g 65534 nobody >/dev/null 2>/dev/null
+fi