Expanded storage cannot be defined for a CF image. Only IBM CFCC can run in CF  mode. In Linux only mode, storage addressing can be 31 bit or 64 bit, depending on the operating  system architecture and the operating system configuration. Only Linux and z/VM operating systems can run in Linux only mode. Linux on Z 64-bit  distributions (SUSE Linux Enterprise Server 10 and later, Red Hat RHEL 5 and later, and  Ubuntu 16.04 LTS and later) use 64-bit addressing and operate in z/Architecture mode.  z/VM also uses 64-bit addressing and operates in z/Architecture mode. In z/VM mode, certain types of processor units can be defined within one LPAR. This  feature increases flexibility and simplifies systems management by allowing z/VM to run  the following tasks in the same z/VM LPAR: GLYPH<SM590000> Linux only mode GLYPH<SM590000> z/VM mode GLYPH<SM590000> Secure Service Container (SSC) mode – Manage guests to operate Linux on Z on IFLs – Operate z/VSE and z/OS on CPs – Offload z/OS system software processor usage, such as Db2 workloads on zIIPs – Provide an economical Java execution environment under z/OS on zIIPs GLYPH<SM590000> The  initial value  is the storage size that is allocated to the partition when it is activated. GLYPH<SM590000> The  reserved value  is another storage capacity beyond its initial storage size that an LPAR  can acquire dynamically. The reserved storage sizes that are defined to an LPAR do not  need be available when the partition is activated. They are predefined storage sizes to  allow a storage increase, from an LPAR point of view. 1. Partition deactivation. 2. An initial storage size definition change. 3. Partition activation. In SSC mode, storage addressing is 64 bit for an embedded product. This configuration  allows for an addressing range up to 16 EB. However, the current z14 ZR1 definition limit  for LPARs is 8 TB of storage (physical memory limit). Currently, the z/VSE Network Appliance (available on z14 ZR1) runs in an SSC LPAR. Reserved storage can be optionally defined to an LPAR, which allows a nondisruptive image  memory upgrade for this partition. Reserved storage can be defined to central and expanded  storage, and to any image mode except CF mode. An LPAR must define an amount of main storage and optionally (if not a CF image), an  amount of expanded storage. Main storage and expanded storage can have the following  storage sizes defined: Without the reserved storage definition, an LPAR storage upgrade is a disruptive process that  requires the following steps: 3.7.3 Reserved storage The extra storage capacity for an LPAR upgrade can come from the following sources: GLYPH<SM590000> Any unused available storage GLYPH<SM590000> Another partition that features released storage GLYPH<SM590000> A memory upgrade Chapter 3. Central processor complex system design  105