I will buy dinner for anyone that can help me solve this problem:
Now the problem:
Every now and again these Macs drop off the network randomly and the only solution is to unbind and rebind.
Things i've tried:
1. Using a preferred server for domain and set that same server for Time synchronisation
2. Set pass interval to 0 (this is recommended if you don't want it to check the machine password every 14 days with AD)
3. Set manual IP addresses then reverted back to DHCP (on that VLAN)
4. Cleared ALL DNS entries, cleared caches etc
5. Using a domain that does NOT end in .local
6. Disabled bonjour advertising services (to completely disable the .local issue even though I know I'm not using a .local domain)
7. Altered the mdns_timeout period in the file /System/Library/SystemConfiguration/IPMonitor.bundle/Contents/Info.plist (again i know this is for .local domain issues)
8. Tried Centrify Express just as a binding tool
9. Taken them ALL off the VLAN and back on after finding out it makes no difference.
Just as a side note does anybody know why Apple decided to remove the red dot (the traffic light indicating system thing)? I'm talking about the "Network Accounts are unavailable" red dot (Stays on until they do become available). In Mavericks its just a little pop-up flag that displays the same message but disappears instantly when the user starts to type username and obviously if they haven't waited long enough they get the infamous "shake" of the window.
Would be grateful of any advice/suggestions.