Active Directory Plugin AD/OD Integration Fix
Beat my head against the wall over this for quite a while...
If your hostname, mymac.company.com does not match the active directory that you are binding to, say mymac.activedirectory.ad, when you configure the AD plugin it'll work for about 5 minutes and then die. The problem lies in /Library/Preferences/edu.mit.Kerberos. When the AD plugin configures this will it will add two entries to the [domain_realm] section, both company.com (from the hostname) and activedirectory.ad (the Active Directory domain that you're binding to). It'll look something like this...
[domain_realm]
.company.com = COMPANY.COM
.activedirectory.ad = ACTIVEDIRECTORY.AD
If this is the case, you need to change the file to this...
[domain_realm]
.activedirectory.ad = ACTIVEDIRECTORY.AD
and then comment out the two lines at the top of the file to prevent the AD plugin from overwriting the file. Once this is done you can then restart Directory Services via "sudo killall DiretoryService", test your AD lookups by using something like "id username@activedirectory.ad" and you should get a bunch of user information; your AD plugin should work from now on.