This section provides an overview of snapshots for L-Servers.
Snapshot is the function that saves the state and configuration of an L-Server disk at the time the snapshot is taken. When using virtual L-Servers, the snapshot function of server virtualization software is used.
Restoring a collected snapshot restores the following L-Server parameters to their state when the snapshot was taken.
Number of CPUs
CPU Performance
CPU Shares
Memory Size
Memory Shares
Operating System Type
Configuration and Size of the Disk
Network
OS Settings
Information
The following parameters cannot be restored using the snapshot function of the server virtualization software. Therefore, change L-Server specifications to restore those parameters using their values at the time the snapshot was taken.
[VMware]
CPU Reserved
CPU Shares
Memory Reserved
Memory Shares
[Hyper-V]
Operating System Type
These parameters may return to their values at the time that the snapshot was taken even when the restoration process is aborted. Check the L-Server parameters, and modify the specifications as necessary.
Note
If the OS of the L-Server is Linux, the user name and password used when collecting the snapshot will be saved.
It is recommended to change the password after collecting a snapshot to maintain security.
[VMware]
CPU reservation performance and memory reservation capacity are not restored. Changing this value may prevent an L-Server from starting, depending on the amount of resources used by other VM guests on the same VM host.
If multiple snapshots are collected of the same L-Server, the snapshots are managed by automatically adding version numbers to the snapshot file name starting from 1. If the number of snapshot versions exceeds the limit (standard limit is 3), the oldest snapshot will be deleted. Use the rcxadm imagemgr command to change the maximum number of snapshot versions.
For details on the rcxadm imagemgr command, refer to "5.9 rcxadm imagemgr" in the "Reference Guide (Command/XML) CE".
To collect a snapshot, it is recommended that the power of the L-Server is "OFF" to avoid any inconsistencies occurring in the data and file system on the disk.
When collecting a snapshot from an L-Server that is running, the L-Server must be configured in advance for live collection of snapshots.
For details on the settings required to collect a snapshot when the server is running, refer to the manual of the server virtualization software.
For details on operations using the rcxadm image command, refer to "4.1 rcxadm image" in the "Reference Guide (Command/XML) CE".
Note
Immediately after a snapshot is restored, there may be differences between the configuration of VM guests managed by L-Server and those managed by VM management software.
The differences in VM guest configuration are reflected on the configuration of the L-Server by periodic queries made to the VM management software.
For details on reflection of L-Server configuration by periodic queries, refer to "17.2 Modifying an L-Server".
[Physical Servers]
When using physical L-Servers, snapshots cannot be used.
[Hyper-V]
When using Hyper-V, refer to "C.3.11 Advisory Notes for Hyper-V Usage" in the "Setup Guide CE".
[Xen]
When using RHEL5-Xen, snapshots cannot be used.
Collect L-Server snapshots using PRIMECLUSTER GDS.
For details, refer to "C.4.7 Advisory Notes for RHEL5-Xen Usage" in the "Setup Guide CE".
[KVM] [Oracle VM] [Solaris Containers]
Snapshots cannot be used.
Information
The snapshot function provided by server virtualization software records the disk from the last update. Consequently, when a disk failure occurs, the snapshot function becomes unavailable at the same time. Snapshot can be used as a corrective measure for problems such as the following:
Example
For recovery when a problems occurs with the applied patch
For recovery when a problem occurs when changing operating system parameters
Collection
This section explains how to collect a snapshot.
Right-click the target L-Server in the orchestration tree, and select [Snapshot]-[Collect] from the popup menu.
The [Create a Snapshot] dialog is displayed.
Enter the following items:
Enter a comment that identifies the snapshot.
Up to 128 characters other than percent signs ("%"), back slashes ("\"), double quotes ("), and line feed characters can be specified.
The snapshot is collected.
Click <OK>.
From the command-line, execute rcxadm image snapshot.
For details on the rcxadm image snapshot command, refer to "4.1 rcxadm image" in the "Reference Guide (Command/XML) CE".
Restore
This section explains how to restore a snapshot.
To restore a snapshot, the L-Server must be stopped.
Right-click the target L-Server in the orchestration tree, and select [Snapshot]-[Restore] from the popup menu.
The [Restore a Snapshot] dialog is displayed.
Select the version of the snapshot to restore.
The snapshot is restored.
Click <OK>.
Execute the rcxadm image restore command.
For details on the rcxadm image restore command, refer to "4.1 rcxadm image" in the "Reference Guide (Command/XML) CE".
Note
In the following cases, the specifications of the L-Server will not be modified. Use the server virtualization software to make changes as necessary.
When the VM guest corresponding to the L-Server to be restored has been migrated to a VM host that is not registered with Resource Orchestrator
When restoring a snapshot which was taken using:
Resource Orchestrator V2.2.2 or earlier
Resource Orchestrator V.2.3.0 without the following patches applied:
T005433WP-03 [Windows]
T005567LP-01 [Linux]
Deletion
This section explains how to delete unnecessary versions of snapshots.
Right-click the target L-Server in the orchestration tree, and select [Snapshot]-[Delete] from the popup menu.
The [Delete a Snapshot] dialog is displayed.
Select the version of the snapshot to delete.
The snapshot is deleted.
Click <OK>.
From the command-line, execute rcxadm image delete.
For details on the rcxadm image delete command, refer to "4.1 rcxadm image" in the "Reference Guide (Command/XML) CE".
