[CentOS] Re: XDMCP - no GDM login, only gray screen with X

[Sean Carolan]

> I should add to this that I'm able to run X-windows programs on my
> local workstation, such as gnome-terminal, xclock, etc.  Xming opens
> them up with no issues whatsoever.  It's just that I can't get a gdm
> login screen when trying to connect via xdmcp.

If it's any help here is what I see in the /var/log/messages file with
debug turned on.  IP address and hostname have been changed to protect
the innocent:

Oct  1 20:24:22 server gdm[14790]: gdm_xdmcp_decode: Received opcode
QUERY from client 10.10.10.10
Oct  1 20:24:22 server gdm[14790]: gdm_xdmcp_handle_query: Opcode 2
from 10.10.10.10
Oct  1 20:24:22 server gdm[14790]: gdm_xdmcp_send_willing: Sending
WILLING to 10.10.10.10
Oct  1 20:24:23 server gdm[14790]: gdm_xdmcp_decode: Received opcode
REQUEST from client 10.10.10.10
Oct  1 20:24:23 server gdm[14790]: gdm_xdmcp_handle_request: Got
REQUEST from 10.10.10.10
Oct  1 20:24:23 server gdm[14790]: gdm_xdmcp_handle_request:
xdmcp_pending=0, MaxPending=4, xdmcp_sessions=0, MaxSessions=16,
ManufacturerID=
Oct  1 20:24:23 server gdm[14790]: gdm_xdmcp_display_dispose_check
(cpe-10-10-10-10.austin.res.rr.com:0)
Oct  1 20:24:23 server gdm[14790]: gdm_auth_secure_display: Setting up
access for cpe-10-10-10-10.austin.res.rr.com:0
Oct  1 20:24:23 server gdm[14790]: gdm_auth_secure_display: Setting up access
Oct  1 20:24:23 server gdm[14790]: gdm_auth_secure_display: Setting up
access for cpe-10-10-10-10.austin.res.rr.com:0 - 1 entries
Oct  1 20:24:23 server gdm[14790]: gdm_xdmcp_display_alloc:
display=cpe-10-10-10-10.austin.res.rr.com:0, session id=-246206558,
xdmcp_pending=1
Oct  1 20:24:23 server gdm[14790]: gdm_xdmcp_send_accept: Sending
ACCEPT to 10.10.10.10 with SessionID=-246206558
Oct  1 20:24:23 server gdm[14790]: gdm_xdmcp_decode: Received opcode
MANAGE from client 10.10.10.10
Oct  1 20:24:23 server gdm[14790]: gdm_xdmcp_handle_manage: Got MANAGE
from 10.10.10.10
Oct  1 20:24:23 server gdm[14790]: gdm_xdmcp_handle_manage: Got
Display=0, SessionID=-246206558 Class=MIT-unspecified from 10.10.10.10
Oct  1 20:24:23 server gdm[14790]: gdm_xdmcp_handle_manage: Looked up
cpe-10-10-10-10.austin.res.rr.com:0
Oct  1 20:24:23 server gdm[14790]: gdm_choose_indirect_lookup: Host
10.10.10.10 not found
Oct  1 20:24:23 server gdm[14790]: gdm_forward_query_lookup: Host
10.10.10.10 not found
Oct  1 20:24:23 server gdm[14790]: gdm_display_manage: Managing
cpe-10-10-10-10.austin.res.rr.com:0
Oct  1 20:24:23 server gdm[14790]: loop check: last_start 0, last_loop
0, now: 1222907063, retry_count: 0
Oct  1 20:24:23 server gdm[14790]: Resetting counts for loop of death detection
Oct  1 20:24:23 server gdm[14790]: gdm_display_manage: Forked slave: 14864
Oct  1 20:24:23 server gdm[14864]: gdm_slave_start: Starting slave
process for cpe-10-10-10-10.austin.res.rr.com:0
Oct  1 20:24:23 server gdm[14864]: gdm_slave_start: Loop Thingie
Oct  1 20:24:23 server gdm[14864]: gdm_slave_run: Opening display
cpe-10-10-10-10.austin.res.rr.com:0