diff --git a/Add-new-dns-hostnames.md b/Add-new-dns-hostnames.md
index 01c2f1a..c1cd1ed 100644
--- a/Add-new-dns-hostnames.md
+++ b/Add-new-dns-hostnames.md
@@ -28,3 +28,6 @@ Test
 
 * `ping home.mydomain.de` will only work if ip 192.168.1.15 is a machine that accepts pings
 
+A dns flush may be needed to check for the new ip.
+
+* mac/linux flush https://help.dreamhost.com/hc/en-us/articles/214981288-Flushing-your-DNS-cache-in-Mac-OS-X-and-Linux