IBM Copy Services Manager introduction
This chapter provides an overview of IBM Copy Services Manager for IBM Z and open systems. It reviews copy services functions and describes how these functions are implemented in IBM Copy Services Manager (CSM).
We provide an overview for IBM Copy Services Manager key concepts, architecture, session types and usage, and new functionality as of IBM Copy Services Manager version 6.1.
We also introduce IBM Storage Systems that are supported by IBM Copy Services Manager.
The following topics are described in this chapter:
1.1 Overview
IBM Copy Services Manager (formerly IBM Tivoli Storage Productivity Center for Replication, a component of IBM Tivoli Storage Productivity Center and IBM SmartCloud® Virtual Storage Center) manages copy services in IBM storage environments. Copy services are features that are used by storage systems to configure, manage, and monitor data replication functions. These copy services include IBM FlashCopy®, Metro Mirror, Global Mirror, and Metro Global Mirror data replication.
Figure 1-1 on page 3 depicts an overview of the IBM Copy Services Manager environment.
•IBM System Storage® DS8000® series
•IBM Spectrum Storage™:
– IBM Spectrum Virtualize™:
• IBM SAN Volume Controller
• IBM Storwize® Family:3
- IBM Storwize V5000 and V5000F
- IBM Storwize V7000 and V7000F
- IBM Storwize V7000 Unified
- IBM Storwize V7000 and V7000F
- IBM Storwize V7000 Unified
• IBM FlashSystem® V9000
– IBM Spectrum Accelerate™:
• IBM FlashSystem A9000/A9000R4
• IBM XIV® System Storage2
IBM Copy Services Manager automates key replication management tasks to help you improve the efficiency of your storage replication. You can use a simple GUI to configure, automate, manage, and monitor all important data replication tasks in your environment, including the following tasks:
•Manage and monitor multisite environments to meet disaster recovery (DR) requirements
•Automate the administration and configuration of data replication features
•Keep data on multiple related volumes consistent across storage systems in a planned or unplanned outage
•Recover to a remote site to reduce downtime of critical applications
•Provide high availability (HA) for applications by using IBM HyperSwap technology
•Practice recovery processes while disaster recovery capabilities are maintained
Figure 1-1 IBM Copy Services Manager: Managed IBM Storage Systems overview
1.2 New features in CSM 6.1
IBM Copy Services Manager 6.1 new features are provided in releases. At the time of this document, the release available was 6.1.4.
See the following product documentation for a list of new products and features.
Release Notes can be found at the Fix Central website.
|
Important: To access Release Notes information from IBM Support, you might need to authenticate using your IBM ID. If you do not have one, register.
|
1.3 Terminology
In this section, we describe the following key terms to help you understand and effectively use IBM Copy Services Manager:
•Management server
The management server is a system that has IBM Copy Services Manager Server code installed. The management server provides a central point of control for managing data replication.
You can create a high availability environment by setting up a standby management server. A standby management server is a second instance of IBM Copy Services Manager server that runs on a different physical system, but is continuously synchronized with the primary (or active) IBM Copy Services Manager server.
The active management server issues commands and processes events, while the standby management server records the changes to the active server. As a result, the standby management server contains identical data to the active management server and can take over and run the environment without any loss of data.
•Storage system
A storage system is a hardware device that contains data storage. Copy Services Manager (CSM) can control data replication within and between various storage systems. To replicate data among storage systems by using CSM, you must manually add a connection to each storage system.
•Host system
A host system is an AIX or IBM z/OS system that connects to storage systems to enable certain replication features for those systems.
A connection to a z/OS host system is required if you want to enable z/OS features, such as HyperSwap and hardened freeze in CSM sessions.
A connection to an AIX host system is required if you want to use the Open HyperSwap5 feature. This feature enables the automatic swap of input/output (I/O) to the volumes on a secondary site when a failure occurs when I/O is written to the primary site.
•Users and groups
Copy Services Manager does maintain a directory of user names and passwords. CSM can also be configured to use a Lightweight Directory Access Protocol (LDAP) repository for user authentication.
You can use the CSM graphical user interface (GUI) or command-line interface (CLI) to assign the users and groups that are defined in the user repository to a user role.
•User roles
A user role determines the tasks and sessions that a user or group can manage. Copy Services Manager provides a set of predefined user roles: Monitor, Operator, and Administrator.
– Administrators have unrestricted access to all features and functions in CSM.
– Operators can manage specific sessions.
– Monitors can view information in the CSM; however, they cannot modify or perform any commands or actions.
•Global Copy
For DS8000 storage systems, Global Copy is an asynchronous long-distance copy option for data migration and backup.
•Session
A session completes a specific type of data replication for a specific set of volumes. During data replication, data is copied from a source volume to one or more target volumes, depending on the session type. The source volume and target volumes that contain copies of the same data are collectively referred to as a copy set. A session can contain one or more copy sets. The type of data replication that is associated with the session determines the actions that you can perform against all copy sets in the session, the number of volumes that a copy set can contain, and the role that each volume plays.
•Copy set
A copy set is a set of volumes that represent copies of the same data. During data replication, data is copied from a source volume to one or more target volumes, depending on the session type. The source volume and target volumes that contain copies of the same data are collectively referred to as a copy set.
Each volume in a copy set must be of the same size and volume type. For example, SAN Volume Controller volumes must be used with other SAN Volume Controller volumes. The number of volumes in the copy set and the role that each volume plays is determined by the session type that is associated with the session to which the copy set belongs.
•Volume roles
Volume roles are given to every volume in the copy set.
The volume role types are host volume, journal volume, intermediate volume, target volume, and change volume (SAN Volume Controller or Storwize storage systems only).
The role defines how the volume is used in the copy set and the site location of the volume. For example, a host volume at the primary site has the role of Host1 (H1), while a journal volume at the secondary site has the role of Journal2 (J2).
•Role pair
A role pair is the association of two roles in a session that take part in a copy relationship. For example, in a Metro Mirror session, the role pair can be the association between the volume roles of Host1 and Host2.
•Site
The site determines the location of the volumes. The number of sites in a copy set is determined by the session type. IBM Copy Services Manager supports up three sites:
– Site 1: The location of the primary storage system that contains the source data. Upon initial configuration, this site contains the host volumes with updates that are copied to the target volumes.
– Site 2: The location of the secondary storage system that receives the copy updates from the primary storage system.
– Site 3: The location of the tertiary storage system that receives the copy updates from either the primary or the secondary storage system (Multi-target sessions).
•Host volume
A host volume is a volume that is connected to a server that reads and writes input/output (I/O). A host volume can be the source of updated tracks when the server that is connected to the host volume is actively issuing read and write I/O. A host volume can also be the target of the replication. When the host volume is the target, writes are inhibited.
Host volumes are abbreviated as Hx, where x identifies the site.
•Journal volume
A journal volume stores data that changed since the last consistent copy was created. This volume functions like a journal and holds the required data to reconstruct consistent data at the Global Mirror remote site. When a session must be recovered at the remote site, the journal volume is used to restore data to the last consistency point. A FlashCopy replication session can be created between the host or intermediate volume and the corresponding journal volume after a recover request is started to create another consistent version of the data.
Journal volumes are abbreviated as Jx, where x identifies the site.
•Intermediate volume
An intermediate volume receives data from the primary host volume during a replication with practice session. During a practice, data on the intermediate volumes is flash copied to the practice host volumes.
Depending on the replication method that is used, data on intermediate volumes might not be consistent.
Intermediate volumes are abbreviated as Ix, where x identifies the site.
•Target volume
A target volume receives data from a host or intermediate volume. Depending on the replication type, that data might or might not be consistent. A target volume can also function as a source volume. For example, a common use of the target volume is as a source volume to allow practicing for a disaster, such as data mining at the recovery site while still maintaining disaster recovery capability at the production site.
•Change volume
A change volume contains point-in-time images that are copied from the host or target volume.
Change volumes are abbreviated as Cx, where x identifies the site.
1.4 Architecture
IBM Copy Services Manager high-level architecture is shown in Figure 1-2 .
Figure 1-2 IBM Copy Services Manager high level architecture
Connectivity to storage systems is provided as follows:
•IBM Enterprise Storage Server® Network Interface (ESSNI) for the DS8000 series
•Remote commands on Secure Shell for IBM Spectrum Virtualize and IBM Spectrum Accelerate storage systems.
The IBM Copy Services Manager is implemented as an application using the IBM WebSphere® Liberty framework and Apache Derby database.
1.5 Managed storage systems and session types
Copy Services Manager controls data replication within and between various storage systems. All storage systems are grouped into site locations. The relationships between replicated volumes are managed by sessions. A session is used to complete a specific type of data replication against a specific set of volumes.
The type of copy service that is associated with the session determines the replication actions that are available for the session. For example, the options for FlashCopy sessions are different from the options for Metro Mirror sessions.
So, one session has the following components:
•One or more sites
•One or more storage systems
•One or more copy sets
When copy sets are added to the session, only the storage systems whose location matches the location of the site are allowed for selection. This ensures that a session relationship is not established in the wrong direction.
Table 1-1 shows the session types that are available in CSM 6.1.x and the storage systems that are supported.
Table 1-1 Sessions types and supported storage systems
|
Session name
|
Spectrum Virtualize1
|
Spectrum Accelerate2
|
ESS/DS8K
|
HyperSwap Function
|
|
Single site
|
||||
|
FlashCopy
|
Yes
|
N/A
|
yes
|
N/A
|
|
Snapshot
|
N/A
|
Yes
|
N/A
|
N/A
|
|
Dual site synchronous
|
||||
|
Basic HyperSwap
|
N/A
|
N/A
|
Yes3
|
N/A
|
|
Metro Mirror Single Direction
|
Yes
|
N/A
|
N/A
|
N/A
|
|
Metro Mirror Failover/Failback
|
Yes
|
Yes
|
Yes
|
Yes
|
|
Metro Mirror Failover/Failback with Practice
|
Yes
|
N/A
|
Yes
|
Yes
|
|
Dual site asynchronous
|
||||
|
Global Mirror Single Direction
|
Yes
|
N/A
|
Yes
|
N/A
|
|
Global Mirror Failover/Failback
|
Yes
|
Yes
|
Yes
|
N/A
|
|
Global Mirror Failover/Failback with Change Volumes
|
Yes
|
N/A
|
N/A
|
N/A
|
|
Global Mirror Failover/Failback with Practice
|
Yes
|
N/A
|
Yes
|
N/A
|
|
Global Mirror Either Direction with Two-Site Practice
|
N/A
|
N/A
|
Yes
|
N/A
|
|
Multitarget sessions
|
||||
|
Metro Mirror - Metro Mirror
|
N/A
|
N/A
|
Yes4
|
Yes
|
|
Metro Mirror - Global Mirror
|
N/A
|
N/A
|
Yesd
|
Yes
|
|
Metro Mirror - Global Mirror with practice
|
N/A
|
N/A
|
Yesd
|
Yes
|
|
Metro Mirror - Global Mirror with Site 3 Global Mirror5
|
N/A
|
N/A
|
Yesd
|
Yes
|
1 SVC, V5000, V7000, and V9000
2 XIV and A9000
3 Available only for z/OS
4 Available only for DS8000 series
5 Available in 6.1.4
1.5.1 Practice sessions
By using practice sessions, you can test disaster-recovery actions while maintaining disaster-recovery capability. In addition, the target volumes can be used for other purposes (for example, patch testing and so on).
Practice sessions include intermediate volumes on the remote site that contains the target volumes. A FlashCopy operation is completed from the intermediate volumes to the target volumes. The target volumes contain point-in-time data that you can use to test data-recovery actions.
For example, you can run scripts that map the target volumes to host systems in a remote site, or complete an initial program load (IPL) on the host in an isolated environment (for example, using different IPs). Because data replication continues from the source volume to the intermediate volume in a normal manner, your data is recoverable while you are testing the practice volume.
To use practice volumes, the session must be in the Prepared state.
|
Practice sessions:
•When practice sessions are used, Copy Services Manager assumes that the set of volumes that are used for practicing is also used in case of actual recovery. For this reason, the IBM Copy Services Manager operations and storage resources that are used for practicing are the same with a real recovery or site switch. This approach relieves the unpredictably of untested procedures during the real recovery operations.
•You can test disaster-recovery actions without the use of practice volumes. However, if you do not use practice volumes, data replication between sites is interrupted while you are recovering data to the remote site.
•Any existent session can be “upgraded” to use practices. However, on the new session, the old target volume becomes Intermediary (I), and the new target is a newly created FlashCopy volume.
|
1.5.2 Monitoring sessions icons and symbols
This section presents the icons and symbols used in the IBM Copy Services Manager GUI.
Session status icons
The Copy Services Manager GUI uses icons to represent the status of each session. Table 1-2 describes each session status icon.
Table 1-2 Session status icons
|
Icon
|
Meaning
|
Description
|
 |
Inactive
|
The session is in a defined state, with no activity on the hardware.
|
 |
Normal
|
A consistent copy of the data either exists or is being maintained.
|
 |
Warning
|
For Metro Mirror, Global Mirror, and Metro Global Mirror, the session might have volumes that are being synchronized or are about to be synchronized, with no suspended volumes. For FlashCopy, the warning status is valid only after the start command is issued and before the flash. This warning status means that the session is either preparing or is ready for a flash command, but targets do not yet have a consistent copy.
If a HyperSwap session is degraded, which means it is enabled on one or more sysplex members and disabled on at least one sysplex member, then the session is in a warning state.
|
 |
Severe
|
One or more errors must be dealt with immediately. Possible causes include the following:
•One or more volumes are suspended
•A session is suspended
•A volume is not copying correctly
|
Volume role symbols
The Copy Services Manager GUI also provides a visual aid to help you create and manage your sessions. The visual aid shows the number of volume roles in the session and how the roles are distributed between the sites. The volume role symbols represent the replication status on the volumes.
Table 1-3 presents the meaning of each volume role symbol.
Table 1-3 Volume role symbols
|
Symbol
|
Description
|
Meaning
|
 |
Active host volumes
|
This symbol represents volumes that contain the source of updated tracks to which the application is actively issuing read and write input/output (I/O).
|
 |
Active host volumes with change volumes
|
This symbol represents volumes that contain the source of updated tracks to which the application is actively issuing read and write I/O and change volumes.
|
 |
Recoverable volumes
|
This symbol represents volumes that contain a consistent copy of the data.
|
 |
Recoverable volumes with change volumes
|
This symbol represents volumes and change volumes that contain a consistent copy of the data.
|
 |
Inconsistent volumes
|
This symbol represents the volumes that do not contain a consistent copy of the data.
|
 |
Inconsistent volumes with change volumes
|
This symbol represents the volumes and change volumes that do not contain a consistent copy of the data.
|
Data copying symbols
The Copy Services Manager GUI also shows the copy method and direction. The data copying symbols indicate the type of copy that occurs between the volume roles. The direction that the symbol is displayed in the Copy Services Manager GUI depends on the direction of the copy.
Table 1-4 presents the meaning of each data copying symbol.
Table 1-4 Data copying symbols
|
Symbol
|
Description
|
Meaning
|
 |
FlashCopy
|
This symbol represents a FlashCopy operation.
|
 |
FlashCopy with errors
|
This symbol represents a FlashCopy operation with errors on one or more pair.
|
 |
FlashCopy inactive
|
This symbol represents an inactive FlashCopy operation.
|
 |
FlashCopy inactive with errors
|
This symbol represents an inactive FlashCopy operation with errors on one or more pair.
|
 |
Synchronous
|
This symbol represents a synchronous copy.
|
 |
Synchronous with errors
|
This symbol represents a synchronous copy with errors on one or more pairs.
|
 |
Synchronous inactive
|
This symbol represents an inactive synchronous copy.
|
 |
Synchronous inactive with errors
|
This symbol represents an inactive synchronous copy with errors on one or more pair.
|
 |
Asynchronous
|
This symbol represents an asynchronous copy.
|
 |
Asynchronous with errors
|
This symbol represents an asynchronous copy with errors on one or more pair.
|
 |
Asynchronous inactive
|
This symbol represents an inactive asynchronous copy.
|
 |
Asynchronous inactive with errors
|
This symbol represents an inactive asynchronous copy with errors on one or more pair.
|
 |
HyperSwap or Open HyperSwap
|
This symbol indicates that the HyperSwap or Open HyperSwap feature is enabled for the relationship. If a failure occurs when I/O is being written to the primary storage system, these features automatically swap the I/O to the secondary site with no user interaction and little or no effect on the application.
|
 |
Suspended
|
This symbol represents a suspended copy relationship.
|
 |
Failed over
|
This symbol represents a failover copy relationship.
|
1.5.3 Session types
This section provides a brief description of the copy services session types and their associated icons in the CSM GUI.
FlashCopy
FlashCopy (see Table 1-1 on page 7) sessions copy the data that is on the source volume to the target volume on the same site (Site 1). The target volume contains the same data as the source volume at the point in time when the copy was established. Any subsequent write operations to the source volume are not reflected on the target volume. Figure 1-3 shows the volumes and data flow for the session.
Figure 1-3 FlashCopy session pictogram
Snapshot
Snapshot sessions (see Table 1-1 on page 7) create a point-in-time copy of a volume or set of volumes on the same site (Site 1) without having to define a specific target volume. The target volumes of a Snapshot session are automatically created when the snapshot is created. Figure 1-4 shows the volumes for the session.
Figure 1-4 Snapshot session pictogram
Metro Mirror Single Direction
Metro Mirror Single Direction sessions copy data in a single direction from the source volume on the local site (Site 1) to the target volume on the remote site (Site 2). Figure 1-5 shows the volumes and data flow for the session when data is copied from Site1 to Site 2.
Figure 1-5 Metro Mirror single direction session pictogram
Metro Mirror Failover/Failback
Metro Mirror Failover/Failback sessions provide the same capabilities as Metro Mirror Single Directions sessions. The difference is that data replication for Metro Mirror Failover/Failback sessions is bidirectional.
Figure 1-6 shows the volumes and data flow for the session when data is copied from Site 1 to Site 2.
Figure 1-6 Metro Mirror failover and failback session pictogram
Basic HyperSwap
Basic HyperSwap sessions provide the same capabilities as Metro Mirror Failover/Failback session. A new HyperSwap function is added which commands the Z HyperSwap to switch I/O operations to the other site. Figure 1-7 shows the volumes and data flow for the session and also the HyperSwap sign.
Figure 1-7 Basic HyperSwap session pictogram
Metro Mirror Failover/Failback with Practice
Metro Mirror Failover/Failback with Practice sessions combine Metro Mirror and FlashCopy replication to provide a point-in-time copy of the data on the remote site.
For this session type, a synchronous copy occurs from a source volume on the local site (Site 1) to an intermediate volume on the remote site (Site 2). A FlashCopy then occurs from the intermediate volume to a target volume on the remote site.
Figure 1-8 shows the volumes and data flow for the session when data is copied from Site 1 to Site 2.
Figure 1-8 Metro Mirror failover/failback with practices session pictogram
Global Mirror Single Direction
Global Mirror Single Direction sessions copy data in a single direction from a source volume on the local site (Site 1) to a target volume on the remote site (Site 2).
DS8000 storage systems
For DS8000 storage systems6, an asynchronous copy occurs from the source volume to the target volume. A FlashCopy then occurs from the target volume to a journal volume on the remote site.
Figure 1-9 shows the volumes and data flow for an IBM Enterprise Storage Server, IBM DS6000, or IBM DS8000 Global Mirror Single Direction session when data is copied from Site 1 to Site 2.
Figure 1-9 Global Mirror single direction session pictogram (DS8000 series)
IBM Spectrum Virtualize storage systems
For all other IBM Spectrum Virtualize storage system sessions, the data flow is the same. However, there is no FlashCopy to a journal volume.
Figure 1-10 shows the volumes and data flow for an IBM Spectrum Virtualize Global Mirror Single Direction session when data is copied from Site 1 to Site 2.
Figure 1-10 Global Mirror single direction session pictogram (IBM Spectrum Virtualize)
Global Mirror Failover/Failback
Global Mirror Failover/Failback sessions provide the same capabilities as Global Mirror Single Direction sessions. The difference is that data replication for Global Mirror Failover/Failback sessions is bidirectional.
DS8000 storage systems
Figure 1-11 shows the volumes and data flow for DS8000 Storage Systems7 Global Mirror Single Direction session when data is copied from Site 1 to Site 2.
Figure 1-11 Global Mirror failover/failback session pictogram (DS8000 series)
IBM Spectrum Virtualize storage systems
For all other IBM Spectrum Virtualize storage system sessions, the data flow is the same. However, there is no FlashCopy to a journal volume, as shown in Figure 1-12.
Figure 1-12 Global Mirror failover/failback session pictogram (IBM Spectrum Virtualize)
Global Mirror Failover/Failback with Change Volumes
Global Mirror Failover/Failback with Change Volumes (GMCV) sessions provide the same capabilities as Global Mirror Failover/Failback sessions but designed for lower bandwidth replication links. The difference is that the GMCV session also provides the option of enabling or disabling the use of change volumes.
|
Note: GMCV sessions are available only for IBM Spectrum Virtualize storage systems.
|
Figure 1-13 shows the volumes and data flow for the GMCV session when data is copied from Site 1 to Site 2. C1 and C2 are the change volumes for both sites.
Figure 1-13 GMCV session pictogram
Global Mirror Failover/Failback with Practice
Global Mirror Failover/Failback with Practice sessions combine Global Mirror and FlashCopy replication to provide a point-in-time copy of the data on the remote site (Site 2) for practice purpose.
DS8000 storage systems
For DS8000 storage systems8, an asynchronous copy occurs from the source volume on the local site (Site 1) to an intermediate volume on the remote site (Site 2). A FlashCopy then occurs from the intermediate volume to both the practice volume and the journal volume on the remote site. Figure 1-14 represents the volumes and data flow for DS8000 Global Mirror Failover/Failback with Practice session when data is copied from Site 1 to Site 2.
Figure 1-14 Global Mirror failover/failback session pictogram (DS8000 series)
IBM Spectrum Virtualize storage systems
For all other Spectrum Virtualize storage system sessions, the data flow is the same. However, there is no FlashCopy to a journal volume, as shown in Figure 1-15.
Figure 1-15 Global Mirror failover/failback w/ practice session pictogram (Spectrum Virtualize)
Global Mirror Either Direction with Two-Site Practice
Global Mirror Either Direction with Two-Site Practice sessions combines Global Mirror and FlashCopy replication to provide a point-in-time copy of the data on the local (Site 1) and remote site (Site 2). This session type includes one intermediate volume in each site, the local and remote one, so that you can practice disaster recovery from either site. Figure 1-16 shows the volumes and data flow for the session when data is copied from Site 1 to Site 2. I1 and I2 are the intermediate volumes in both sites.
Figure 1-16 Global Mirror either direction with two-site practice pictogram
Metro Global Mirror (three sites)
|
Note: Metro Global Mirror sessions are available only on DS8000 and ESS storage systems.
|
Metro Global Mirror sessions combine Metro Mirror, Global Mirror, and FlashCopy replication into a single session. Metro Global Mirror sessions support three sites that are varying distances apart.
For this session type, a synchronous copy occurs from the source volume on the local site (Site 1) to the target volume on the second site (Site 2). An asynchronous copy then occurs from the volume in the second site to the target volume on the third site (Site 3) followed by a FlashCopy from the target to the journal volume on the same Site 3.
Figure 1-17 shows the volumes and data flow for the session when data is copied from Site 1 to Site 2 and then to Site 3.
Figure 1-17 Metro Global Mirror session pictogram
Metro Global Mirror with Practice
|
Note: Metro Global Mirror with Practice sessions are available only on DS8000 and ESS storage systems.
|
Metro Global Mirror with Practice sessions combine Metro Mirror, Global Mirror, and FlashCopy replication across three sites to provide a point-in-time copy of the data on the third site.
For this session type, a synchronous copy occurs from the source volume on the local site (Site 1) to the target volume on the second site (Site 2). An asynchronous copy then occurs from the second site to the intermediate volume on the third site (Site 3) followed by a FlashCopy from the intermediate volume to the target and journal volumes on Site 3. Figure 1-18 shows the volumes and data flow for the session when data is copied from Site 1 through Site 3.
Figure 1-18 Metro Global Mirror with Practice session pictogram
Metro Mirror - Metro Mirror (multi-target)
|
Note: Metro Mirror - Metro Mirror sessions are available only for IBM DS8000 storage systems with a microcode level that supports single source to multi-target relationships. To determine whether you can use this session type, refer to the IBM DS8000 documentation for the microcode level that you are using.
|
Metro Mirror - Metro Mirror session is a multi-target session over three sites. One site (Site 1) is defined as source for two different Metro Mirror replications to other sites (Site 2 and Site 3).
Figure 1-19 shows the volumes and data flow for the session when data is copied from Site 1 to Site 2 and Site 3.
Figure 1-19 Metro Mirror - Metro Mirror session pictogram
Metro Mirror - Global Mirror
|
Note: Metro Mirror - Global Mirror sessions are available only for IBM DS8000 storage systems with a microcode level that supports single source to multi-target relationships. To determine whether you can use this session type, refer to the IBM DS8000 documentation for the microcode level that you are using.
|
Metro Mirror - Global Mirror session is a multi-target session against three sites. One site (Site 1) is defined as source for a Metro Mirror replication to second site (Site 2) and for another Global Mirror replication to the third site (Site 3).
Figure 1-20 on page 19 shows the volumes and data flow for the session when data is copied from Site 1 to Site 2 and Site 3.
Figure 1-20 Metro Mirror Global Mirror (multi-target) session pictogram
Metro Mirror - Global Mirror with Practice
|
Note: Metro Mirror - Global Mirror with Practice sessions are available only for IBM DS8000 storage systems with a microcode level that supports single source to multi-target relationships. To determine whether you can use this session type, refer to the IBM DS8000 documentation for the microcode level that you are using.
|
Metro Mirror - Global Mirror with Practice session provide the same capabilities as Metro Mirror - Global Mirror session. In addition, this session uses FlashCopy volumes to practicing disaster recovery without losing your disaster recovery capability. Figure 1-21 shows the volumes and data flow for the session when data is copied from Site 1 to Site 2 and Site 3 and also the practice volumes.
Figure 1-21 Metro Mirror Global Mirror (multi-target) w/ practice session pictogram
Metro Mirror - Global Mirror with Site 3 Global Mirror
|
Note: Metro Mirror - Global Mirror with Site 3 Global Mirror sessions are available only for IBM DS8000 storage systems with a microcode level that supports single source to multi-target relationships. To determine whether you can use this session type, refer to the IBM DS8000 documentation for the microcode level that you are using.
|
Metro Mirror - Global Mirror with Site 3 Global Mirror session provide the same capabilities as Metro Mirror - Global Mirror. In addition, after recovery in the third site (Site 3), this session allows a Global Mirror replication back to either primary site (Site 1) or secondary site (Site 2) and a cascaded Global Copy to the third site. This action provides disaster recover capabilities while production runs at Site 3. Figure 1-22 shows the volumes and data flow for the session when data is copied from Site 1 to Site 2 and Site 3 and also the journal volumes on each site.
Figure 1-22 Metro Mirror - Global Mirror with Site 3 Global Mirror session pictogram
1.5.4 Session commands
The commands (actions) that are available for a session depend on the session type. Commands are issued synchronously to Copy Services Manager sessions. Any subsequent command that is issued to an individual session is not processed until the first command completes.
Some commands, such as the Start command, can take an extended amount of time to complete. By using the GUI, you can still issue commands to other sessions and not hold up functionality. When a command completes, the GUI console displays the results of the command.
The complete list of session commands with GUI details can be found in IBM Knowledge Center for CSM.
|
Note: The CSM CLI commands use specific syntax. For an example of using the CSM CLI see 2.2, “CSM command-line interface (CLI)” on page 23.
|
1 IBM Copy Services Manager might work with older IBM Storage Systems also. However, we do not list these products anymore because they are at end of service from IBM.
2 Always check the latest information for end of service information for your IBM Storage (hardware and software).
3 See the Storwize data sheet.
4 IBM Copy Services Manager 6.1.4 or later.
5 Open HyperSwap is not supported for AIX host servers that are in a clustered environment such as IBM PowerHA® SystemMirror® for AIX.
6 Also supported on ESS800 and IBM DS6000™
7 Also supported on ESS800 and DS6000
8 Also supported on ESS800 and DS6000
..................Content has been hidden....................
You can't read the all page of ebook, please click here login for view all page.