Update README.md

added statement about file format and example

front/plugins/dhcp_leases/README.md

@@ -29,4 +29,25 @@ DHCPLSS_paths_to_check = ['/mnt/dhcp1.leases','/mnt/dhcp2.leases']
 
 ### Notes
 
-- No specific configuration needed.
+- No specific configuration needed.
+
+- This plugin expects the dhcp.leases file(s) to be in the format of **dhcpd.leases** that is different to the format that PiHole uses. 
+[dhcpd.leases(5) - Linux man page]( https://linux.die.net/man/5/dhcpd.leases#:~:text=This%20database%20is%20a%20free,file%20is%20the%20current%20one.) 
+
+Example File Format:  _(not all lines are required)_
+
+```
+lease 192.168.79.15 {
+  starts 0 2016/08/21 13:25:45;
+  ends 0 2016/08/21 19:25:45;
+  cltt 0 2016/08/21 13:25:45;
+  binding state active;
+  next binding state free;
+  rewind binding state free;
+  hardware ethernet 8c:1a:bf:11:00:ea;
+  uid "\001\214\032\277\021\000\352";
+  option agent.circuit-id 0:17;
+  option agent.remote-id c0:a8:9:5;
+  client-hostname "android-8182e21c852776e7";
+}  
+```