For Linux on Z: Changing the kernel settings

In order for GPFS to run on Linux® on Z, the kernel settings need to be changed.

Before starting GPFS, perform the following steps on each Linux on Z node.
On SLES:
  1. In the /etc/default/grub file, add the following:
    GRUB_CMDLINE_LINUX_DEFAULT=" hvc_iucv=8 TERM=dumb osamedium=eth instmode=ftp x 
crashkernel=206M-:103M cio_ignore=all,!ipldev,!condev vmalloc=4096G "
  2. Run the following command:
    grub2-mkconfig -o /boot/grub2/grub.cfg
  3. Reboot the node.
Start of changeOn Red Hat Enterprise Linux 7:End of change
  1. In the /etc/zipl.conf file, add vmalloc=4096G as shown in the following example:
    [defaultboot]
defaultauto
prompt=1
timeout=5
default=3.10.0-957.el7.s390x
target=/boot
[3.10.0-957.el7.s390x]
image=/boot/vmlinuz-3.10.0-957.el7.s390x
parameters="root=/dev/mapper/system_vg-root 
crashkernel=auto rd.dasd=0.0.0201 
rd.lvm.lv=system_vg/root 
cio_ignore=all,!condev,!0.0.1000-0.0.1002 
rd.znet=qeth,0.0.1000,0.0.1001,0.0.1002,layer2=1 
LANG=en_US.UTF-8 
vmalloc=4096G"
ramdisk=/boot/initramfs-3.10.0-957.el7.s390x.img
  2. Run the zipl command.
    Note: For information about the zipl command, see the topic about the initial program loader for IBM Z® (-zipl) in Device Drivers, Features, and Commands in the Linux on Z library overview.
  3. Reboot the node.
Start of changeOn Red Hat Enterprise Linux 8:End of change
Start of change
  1. Use the grubby utility to add vmalloc=4096G for all boot entries on your node as shown in the following example:
    grubby --update-kernel=ALL --args="vmalloc=4096G"
  2. Run the zipl command.
  3. Reboot the node.
Start of change
On Red Hat Enterprise Linux 8.3:

New kernel parameter dfltcc is supported. This parameter configures the zlib hardware support for IBM Z architectures. This must be kept at the default value on. zlib hardware support is enabled by IBM Spectrum Scale if available.

New kernel parameter prot_virt is supported. This parameter enables the hosting of protected virtual machines that are isolated from the hypervisor if the hardware support is present. IBM Spectrum Scale supports this parameter.

End of change End of change
On Ubuntu:
  1. In the /etc/zipl.conf file, add vmalloc=4096G as shown in the following example:
    [defaultboot]
default=UBUNTU18.04.1
target=/boot

[UBUNTU18.04.1]
target=/boot
image=/boot/vmlinuz
parameters="crashkernel=1G-:128M zfcp.allow_lun_scan=0 
scsi_mod.scsi_logging_level=4605 
printk.time=1 
zfcp.dbfsize=100 
root=/dev/disk/by-path/ccw-0.0.db85-part1 
vmalloc=4096G"
ramdisk=/boot/initrd.img
  2. Run the zipl command.
    Note: For information about the zipl command, see the topic about the initial program loader for IBM Z (-zipl) in Device Drivers, Features, and Commands in the Linux on Z library overview.
  3. Reboot the node.
Note: For more detailed information about installation and startup of GPFS on IBM Z, see the Getting started with IBM Spectrum Scale for Linux on IBM Z white paper, available on the welcome page for IBM Spectrum Scale in IBM® Knowledge Center (www.ibm.com/support/knowledgecenter/STXKQY/ibmspectrumscale_welcome.html).