enable xdmcp centos 6

Below /etc/gdm/custom.conf works for CentOS 5 for enabling xdmcp protocol :

[security]
DisallowTCP=false
AllowRemoteRoot=true
[xdmcp]
Enable=true

However, it doesn’t work for CentOS 6 . It requires an additional line on [greeter] section :

[security]
DisallowTCP=false
AllowRemoteRoot=true
[xdmcp]
Enable=true
[greeter]
IncludeAll=true

If IncludeAll=true , then the face browser will show all users on the local machine. If false, the face browser will only show users who have recently logged in. According to what it means , I really don’t have a clue why this affect our users’ logon . Strange enough …

Enable xdmcp for CentOS 7