The Problem
Rebooting the CentOS/RHEL 8 server causes it to freeze. From the console output, the system is stuck at:
... [ 68.906159] dracut: Disassembling device-mapper devices Rebooting. [ 68.934073] kvm: exiting hardware virtualization [ 68.936622] sd 0:0:0:0: [sda] Synchronizing SCSI cache [ 68.938942] e100e: EEE TX LPI TIMER: 00000011 [ 69.018502] reboot: Restarting system [ 69.020000] reboot: machine restart
After removing “rhgb quiet” and adding “debug rd.debug” in grub command line, following messages appears on reboot:
The Solution
This issue is due to buggy or out-of-specification ACPI firmware. ACPI stands for Advanced Configuration and Power Interface. It is the system that controls hardware actions such as the dynamic speed fans, the power button behavior, system sleep states, and helps to identify some system capabilities.
ACPI power-saving features are hierarchical, meaning that any device running “behind” another will be dependent on the power state of the parent device. For example, a device cannot be running in full power “behind” a device that is sleeping or in standby mode.
Contact Hardware Vendor for upgrading the ACPI firmware/System firmware.
Disabling ACPI
For Workaround: Please follow the below steps for disabling ACPI:
1. Edit /etc/default/grub and add acpi=off in grub command line.
[root@centos8 ~]# cat /etc/default/grub
GRUB_TIMEOUT=5
GRUB_DISTRIBUTOR="$(sed 's, release .*$,,g' /etc/system-release)"
GRUB_DEFAULT=saved
GRUB_DISABLE_SUBMENU=true
GRUB_TERMINAL_OUTPUT="console"
GRUB_CMDLINE_LINUX="crashkernel=auto resume=/dev/mapper/ol-swap rd.lvm.lv=ol/root rd.lvm.lv=ol/swap debug rd.debug acpi=off"
GRUB_DISABLE_RECOVERY="true"
GRUB_ENABLE_BLSCFG=true
2. Regenerate grub configuration file.
# grub2-mkconfig -o /boot/grub2/grub.cfg
3. Manually power-cycle the system.