Update README.md

README.md

@@ -18,6 +18,26 @@ Consequently I began to run my own nameservers (ns1/2.tobiastime.xyz) on two hea
 - PowerDNS
 - Bash
 
+## Workflow
+```
+Cronjob triggers ipsender script on Nginx server
+        ↓
+Nginx server obtains public dynamic IP via curl or dig
+        ↓
+IP is written to a local file
+        ↓
+IP file is transferred to master nameserver via SFTP utilizing a least privileged user
+        ↓
+Cronjob triggers "BashDDNS" script on master nameserver
+        ↓
+BashDDNS checks newly received IP address against current A record IP on file
+        ↓
+Does the new IP match the current record?
+  ↓ Yes               ↓No 
+  Do nothing          Update domain's A record 
+                      Increase SOA serial so slave is notified
+                      Write new IP to stored record file
+```
 
 ## Prerequisites