I have just converted a Fedora Core 5 server to a CentOS 5 Xen Dom0 with Fedora Core 5 as a DomU.
The process took a little longer than expected because I didn’t have console or network access to the DomU initially. It turned out that /etc/modprobe.conf was configured to have the tg3 device for Ethernet while I really needed xennet to get networking going.
The console problem was due to the fact that the device /dev/xvc0 is used for the console in DomU’s and the Fedora Core 5 image was configured for a non-Xen mode of operation. Incidentally it seems a little strange that a default install of CentOS as a DomU will get gettys for /dev/tty[1..6] when none of them seem accessible. After I changed the /etc/inittab file to get the correct name it still didn’t work. It seems that the SE Linux policy in Fedora Core 5 doesn’t have the correct context for the /dev/xvc0 device.
semanage fcontext -a -f -c -s system_u -t tty_device_t /dev/xvc0
So I had to run the above semanage command to change the policy configuration, followed by restorecon /dev/xcv0 to apply the change (although once the change is configured it will apply after the next reboot).