SoftReboot White Paper (766152-001, March 2014)

5 Constraints
Hardware configuration changes
Primary boot path changes
If the boot path is changed using setboot to a different disk, the softreboot should not be invoked.
Instead normal reboot should be issued.
HyperThreading settings
If the hyper threading settings are changed using setboot -m ON/OFF then those settings do
not take effect across a softreboot. To effect the settings, normal reboot without "-S" option should
be done.
nPar hardware setting changes
If the nPar settings like ILM/CLM ratios, cell assignments and so on are changed using the
parmodify command, then those settings do not take effect across a softreboot. To activate these
nPar changes, perform a normal reboot (shutdown/reboot –R/-H).
Cell OLAD
If a floating cell is dynamically deleted using the parolrad command and then a softreboot is
performed, the new kernel OS instance shall not contain the deleted cell. Whereas, upon a normal
reboot, any floating cell deleted using parolrad is available in the next kernel boot. If the deleted
cell is to be made available, then that cell should be added back using "parolrad" or normal
reboot should be attempted instead of softreboot.
Interface card OL* (PCI OL*)
If any PCI card is dynamically deleted using the "olrad" command and then a softreboot is
performed, in the new kernel instance the PCI card shall remain powered OFF. Whereas, upon a
normal reboot, the deleted PCI card is available (powered ON) in the next booted kernel instance.
If the deleted PCI card is to be used in the next kernel boot, add the card explicitly using "olrad"
or perform a normal reboot without -S option.
Dynamic processor resiliency
A processor deactivated by DPR shall remain deactivated in the next boot done through softreboot,
but the processor is not removed until a normal reboot is performed.
Known issues with SoftReboot
• Softreboot kernel loading can fail, if the system has USB and Graphics I/O cards in place.
WARNING! Falling back to normal reboot.
• If icapmodify was run prior to softreboot, the next booted Kernel may not show the correct
number of processor cores. Hence, iCAP is not recommended to be used in combination with
softreboot.
12 Constraints