WARNING, PLEASE NOTE: AIX JFS file systems are not supported on disks that have a sector size of 4 KB. So, if you try to restore a mksysb, that has JFS file systems in rootvg, to a system with 4K disks, it will fail. You will see the following message during the mksysb restore: "Disk block size of 4096 is not supported for this filesystem". For example, you might be trying to migrate (clone) an LPAR to a new POWER9 system that has 4K drives using a mksysb image. You can workaround this by converting your rootvg file systems from JFS to JFS2, using alt_disk_copy, then taking a mksysb to restore to the 4K disks. https://www.ibm.com/developerworks/community/blogs/cgaix/entry/convert_rootvg_file_systems_to_jfs2_using_alt_disk_copy?lang=en  https://www.ibm.com/support/knowledgecenter/en/ssw_aix_72/com.ibm.aix.osdevice/fscompmig.htm