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@@ -1,3 +1,10 @@
 # DNS Zone Files for bremen.freifunk.net and ffhb.de
 
-Run `update-dns-zones.sh` on the DNS server to pull and activate the latest Git repository changes.
+## Editing Zone Files
+If you make changes to any zone file, you must change the `Serial` value (at the top of the file) to a higher value, so that the changes will actually be used.
+Use the current date followed followed by `01` (or a higher number) as the new serial number.
+
+## Applying Changes
+To actually activate any changes, someone with admin access needs to
+* make sure the changes are contained in the "dns" repository on the internal Git server
+* log in on the DNS server and run `update-dns-zones.sh` to pull and activate the latest Git repository changes.