GLYPH<SM590000> Out-of-sync bitmaps share the bitmap space with FlashCopy and Metro Mirror/Global  Mirror. Creating, expanding, and changing I/O groups might fail if there is insufficient  memory. GLYPH<SM590000> GUI views contain volume copy identifiers. GLYPH<SM590000> A mirrored volume is always composed of two copies (copy 0 and copy1).  GLYPH<SM590000> A volume that is not mirrored consists of a single copy (which for reference might be  copy 0 or copy 1).  5.5.3 Mirrored volume components 5.5.4 Volume Mirroring synchronization options Note the following points regarding mirrored volume components: A mirrored volume looks the same to upper-layer clients as a non-mirrored volume. That is,  upper layers within the cluster software, such as FlashCopy and Metro Mirror/Global Mirror,  and storage clients, do not know whether a volume is mirrored. They all continue to handle  the volume as they did before without being aware of whether the volume is mirrored. Figure 5-38 shows the attributes of a volume and Volume Mirroring. In Figure 5-38, XIV and IBM DS8700 illustrate that a mirrored volume can use different  storage devices. As soon as a volume is created with two copies, copies are in the  out-of-sync  state. The  primary volume copy (located in the first specified storage pool) is defined as in sync and the  secondary volume copy as out of sync. The secondary copy is synchronized through the  synchronization process.  Chapter 5. Copy services  273 Figure 5-38 Attributes of a volume and Volume Mirroring Volume ABC  DS8700 Volume ABC Mirroring 0 g DS8700 Striped redundancy Volume ABC Mirroring 1 g XIV Sequential latency Attributes of a Volume: - Volume name - Volume size - Number of copies of the Volume - Volume synchonization rate Volume is accessed by functions: -FlashCopy - Metro Mirror / Global Mirror Attributes of a Mirrored Volume: -Volume copy ID  - 0 or 1 - Physical location (Storage Pool, Mdisk) - Virtualization mode: - Striped, sequential or image - Space allocation policy: - Fully allocated or thin-provisioned - Mirror write priority: code level v6.3 - redundancy - latency