2.4. Post-Installation Instructions
Any installed kernel, both standard and Real Time, can be booted. One way is to select the desired kernel manually in the GRUB menu during booting. Another way is to set the default kernel to the desired one as shown in this section.
- To verify that the Real Time kernel is the default kernel, run as root:
~]#
grubby --default-kernel
/boot/vmlinuz-3.10.0-327.18.2.rt56.223.el7_2.x86_64The rt designation in the above example shows that the default kernel is the Real Time kernel. - To show which kernel the system is currently running, use this command:
~]$
uname -a
Linux rt-server.example.com 3.10.0-327.18.2.rt56.223.el7_2.x86_64 …
- List the installed Real Time kernels:
~]#
ls /boot/vmlinuz*rt*
/boot/vmlinuz-3.10.0-327.18.2.rt56.223.el7_2.x86_64 - Set the default kernel to the listed Real Time kernel by running the following command as root:
~]#
grubby --set-default realtime-kernel
Substitute realtime-kernel with the Real Time kernel version, for example:~]#
grubby --set-default /boot/vmlinuz-3.10.0-327.18.2.rt56.223.el7_2.x86_64
Red Hat Enterprise Linux for Real Time differs substantially from the standard Red Hat Enterprise Linux 7 kernel. As a consequence, third-party kernel modules are incompatible with Red Hat Enterprise Linux for Real Time.
- EMC Powerpath
- NVidia graphics
- Advanced storage adapter configuration utilities from Qlogic
syscall
interface is compatible with Red Hat Enterprise Linux for Real Time.
You can configure Red Hat Enterprise Linux for Real Time to provide crash dump information by enabling kexec/kdump
, if you have not done so for the standard kernel during the installation of Red Hat Enterprise Linux 7. Further information and instructions on how to configure your system to obtain kernel crash information can be found in the Red Hat Enterprise Linux for Real Time Tuning Guide.