PowerHA SystemMirror Version 7.2.2 for Linux Release Notes

New functions and features

PowerHA support on RHEL 7.5
PowerHA® SystemMirror® Version 7.2.2 for Linux is supported on RHEL 7.5.
Note: Support for SAP HANA 2.0 on RHEL for SAP Application 7.5 is not yet tested with PowerHA Linux.
Support for ext4 file systems
PowerHA SystemMirror Version 7.2.2 for Linux with Service Pack 2, or later, supports ext4 type of file systems also in addition to ext3 and xfs.
Support for PowerHA upgrade
PowerHA SystemMirror Version 7.2.2 for Linux with Service Pack 2, or later, support PowerHA upgrade and this is possible with OFFLINE migration.
  • User can migrate PowerHA to a higher version while keeping the cluster configuration intact.
  • During offline migration, the cluster is not available so all the resource groups need to be stopped.
Enhancements in Smart Assist
PowerHA SystemMirror Version 7.2.2 for Linux with Service Pack 2, or later, supports below enhancements:
  1. Smart Assist delete operation is now specific to Application (SAP_HANA etc.).
  2. FQDN support for SAP HANA nodes is added.
PowerHA SystemMirror GUI
The following updates are new in PowerHA SystemMirror GUI with Service Pack 2:
  • Add new clusters as a non-root user. A non-root user will be able to add cluster from PowerHA System Mirror graphical user interface (GUI). For more information, see the Discovering a cluster as a non-root user topic.
  • A secure, single access point to all clusters
  • A health-at-a-glance dashboard that highlights any problems that you need to be aware of
  • Cluster zoning provides unprecedented organization and security
  • High Availability of GUI
  • Snapshot support from GUI
  • Application Monitoring Suspend and Resume feature
  • A clean view of critical cluster and system logs
  • Cluster Modify along with the modification of Resource Group, resources including Service IP, Application or Filesystem
  • The option to authenticate by using an SSH key is now available. SSH authentication is now supported both by private key and passphrase along with password support earlier.
SAP HANA and SAP NetWeaver on same cluster
PowerHA SystemMirror Version 7.2.2 for Linux with Service Pack 1, or later, can run ABAP Central services instance (ASCS) and also database (SAP HANA) on same nodes (2 or 3 nodes). SAP NetWeaver and the database server can be separated into different nodes (4 nodes) when SAP HANA and SAP NetWeaver are running on same cluster. SAP HANA and SAP NetWeaver can be configured in same the cluster, which can create the StartAfter relationship between SAP Application server resource groups and SAP HANA primary resource group.
Support for SAP HANA on RHEL
In PowerHA SystemMirror Version 7.2.2 for Linux with Service Pack 1, or later, the Smart Assist application supports making SAP HANA highly available on RHEL for the SAP solutions.
Support for LDAP
PowerHA SystemMirror Version 7.2.2 for Linux with Service Pack 1, or later, supports OpenLDAP to manage LDAP users and user groups across all PowerHA SystemMirror clusters.
For using OpenLDAP with PowerHA SystemMirror Version 7.2.2 for Linux with Service Pack 1, or later, the following prerequisites are required:
  • OpenLDAP Server must be installed, configured, and must be accessible from all cluster nodes.
  • OpenLDAP Client must be installed and configured on all cluster nodes.

In PowerHA SystemMirror Version 7.2.2 for Linux with Service Pack 1, or later, the user groups provide an additional level of security and enable the system administrators to change the configuration settings of a group of users as a single entity.

Users and user groups can be managed by using the clmgr command from any node in a cluster. The clmgr command sends new and updated information to all of the other nodes in the cluster.

Support for file system on shared storage
PowerHA SystemMirror Version 7.2.2 for Linux with Service Pack 1, or later, supports both the ext3 and xfs type of file systems. PowerHA SystemMirror Version 7.2.2 for Linux with Service Pack 1, or later, allows to add or delete a file system in PowerHA SystemMirror Version 7.2.2 for Linux with Service Pack 1, or later, or system configuration and resource group. The resource group that consist of only file systems as resources supports startup policy to come online on any node in the node list and does not support fallback policy.
Support for resource group reset
If one or more resources in a resource group are in error state (FAILED OFFLINE or STUCK ONLINE), PowerHA SystemMirror Version 7.2.2 for Linux with Service Pack 1, or later, allows to reset all concerned resources currently in error state within same resource group by using the clmgr command to reset a specific resource group.
The resource group must be reset only after the actual issue leading to resource being in an error state is fixed or resolved by user or concerned technical expert.
Support to resource group deletion forcefully

If a resource group cannot be deleted automatically then PowerHA SystemMirror Version 7.2.2 for Linux with Service Pack 1, or later, deletes it forcefully.

However, the deletion of resource group forcefully is not recommended because if any resources in that resource group such as an application or a service_IP are in an error state STUCK ONLINE, then those resources are deleted with an exception of file system.
Updated verification checks for cluster
In PowerHA SystemMirror Version 7.2.2 for Linux with Service Pack 1, or later, the verification process runs the following check:
  • In PowerHA SystemMirror Version 7.2.2 for Linux with Service Pack 1, or later, specific modifications to the Linux system files are correct.
  • The cluster and the corresponding resources are configured correctly.
  • Security is configured correctly.
  • All nodes agree on the cluster topology, network configuration, and the ownership and takeover of PowerHA SystemMirror Version 7.2.2 for Linux with Service Pack 1, or later, resources.
The following new checks are introduced in the verification for PowerHA SystemMirror Version 7.2.2 for Linux with Service Pack 1, or later:
  • Verify the availability of the logical volumes on all cluster nodes.
  • If the file system is mounted, verify the size of logical volumes to know that how much of the logical volume free.
  • Verify whether the same disk is part of multiple file system resources to give an appropriate warning.
  • Verify the availability of volume groups on all cluster nodes.
  • Verify the size of logical volumes on all the cluster nodes.
Support for fully qualified domain name (FQDN)

PowerHA SystemMirror Version 7.2.2 for Linux with Service Pack 1, or later, accepts either the FQDN or corresponding short name as a parameter value for the node name in any of the create or add command.

The node name that is shown in the output of any PowerHA SystemMirror Version 7.2.2 for Linux with Service Pack 1, or later, command other than any add operation like add cluster or add node would be the short name only.

This is valid in case where the cluster nodes are able to correctly resolve the related node name.
  • If the clmgr command is not able to correctly resolve the node name to IP, it aborts the add node or add cluster operation.
  • The node name that is displayed in any further PowerHA SystemMirror Version 7.2.2 for Linux with Service Pack 1, or later, commands would be the short name only.
  • The node name in any further PowerHA SystemMirror Version 7.2.2 for Linux with Service Pack 1, or later, add commands like add resource group or add interface can be either FQDN or the short name.
Support for Japanese language translation

PowerHA SystemMirror Version 7.2.2 for Linux with Service Pack 1, or later, support for Japanese language enables users to be able to interact with the software when the language set on their system is Japanese. To set language the user can export the LC_ALL variable by using the following command: export LC_ALL=Ja_JP for Service pack 1 and export LC_ALL=Ja_JP.utf-8 command for Service Pack 2, or later.

Software requirements

You can download and install the PowerHA SystemMirror Version 7.2.2 for Linux from the IBM® My Entitled Systems Support website.

The cluster node on which you want to install the PowerHA SystemMirror Version 7.2.2 for Linux must be running one of the following versions of the Linux operating system:
  • SUSE Linux Enterprise Server for SAP 12 SP1 (64-bit)
  • SUSE Linux Enterprise Server for SAP 12 SP2 (64-bit)
  • SUSE Linux Enterprise Server for SAP 12 SP3 (64-bit)
  • Red Hat Enterprise Linux (RHEL) 7.2 (64-bit) (Both Little and Big Endian)
  • Red Hat Enterprise Linux (RHEL) 7.3 (64-bit) (Both Little and Big Endian)
  • Red Hat Enterprise Linux (RHEL) 7.4 (64-bit) (Both Little and Big Endian)
  • Red Hat Enterprise Linux (RHEL) 7.5 (64-bit) (Both Little and Big Endian)
Note: PowerHA SystemMirror Version 7.2.2 for Linux is not supported on SLES 11 for SAP.
PowerHA SystemMirror graphical user interface (GUI)

The PowerHA SystemMirror GUI requires OpenSSL installed on the GUI server to generate a unique set of security files (keys and certificate). You must have an installation of Secure Shell (SSH) on the GUI server and on all nodes in the cluster. SSH is used to add clusters to the GUI server, to restore snapshots and to create new clusters.

The PowerHA SystemMirror GUI is supported only on the following web browsers:
  • Google Chrome Version 57, or later
  • Mozilla Firefox Version 54, or later

Installation

For information about installing PowerHA SystemMirror Version 7.2.2 for Linux, see the Installing PowerHA SystemMirror Version 7.2.2 for Linux topic.
Note: If you are on PowerHA SystemMirror Version 7.2.2 for Linux, uninstall this older version to install PowerHA SystemMirror for Linux Version 7.2.2 Service Pack 1 as support for migration from PowerHA SystemMirror on Linux to future releases is provided starting with PowerHA SystemMirror for Linux Version 7.2.2 Service Pack 1.
For information about installing PowerHA SystemMirror graphical user interface (GUI) Version 7.2.2, see the Installing PowerHA SystemMirror GUI topic.
The PowerHA SystemMirror graphical user interface (GUI) has the following limitations in the PowerHA SystemMirror Version 7.2.2 for Linux:
  • If you cannot add or create a cluster, verify that the SSH connection from the PowerHA SystemMirror graphical user interface (GUI) server system to the remote system is working, and does not prompt you for a response. For example: 
    # ssh 172.19.67.49 /bin/hostname 
The authenticity of host ’172.19.67.49 (172.19.67.49)’ can’t be established. 
ECDSA key fingerprint is 41:19:ea:f6:4f:46:91:29:f5:a0:fd:89:91:f7:28:97. 
Are you sure you want to continue connecting (yes/no)?

    In the current version of the PowerHA SystemMirror graphical user interface (GUI), you must respond to the prompt to establish the SSH connection. You must respond by entering yes to add the host to the ~/.ssh/known_hosts file of the PowerHA SystemMirror graphical user interface (GUI) server.

  • Verify that SSH must be configured to allow root access to add existing clusters to the GUI, or create new cluster through the GUI. The SSH configuration setting is PermitRootLogin yes in the /etc/ssh/sshd_config file. You must restart the SSH service.
  • If SSH configuration is not allowing password authentication so either change the SSH config PasswordAuthentication yes in the /etc/ssh/sshd_config file and restart the SSH service or authenticate by using the SSH key.
  • In PowerHA SystemMirror graphical user interface (GUI), you cannot change the host name of any managed cluster node. If you must change the host name of a cluster node that the PowerHA SystemMirror graphical user interface (GUI) server is managing, you might need to remove the cluster from the PowerHA SystemMirror graphical user interface (GUI) server before you change the host name, then add the cluster again after you change the host name. Once you perform this step a single time, you will not have to repeat it for every connection.
  • In PowerHA SystemMirror graphical user interface (GUI), you cannot change the host name of the GUI server host. If you must change the host name of the GUI server, you must either remove all your clusters, rediscover them after you change the host name, or manually update the /usr/es/sbin/cluster/ui/agent/configurationagent.json file on every cluster node and replace the old server IP address with the new address in the server URL. Restart the agent after this update is complete.
  • If you create a cluster by using the PowerHA SystemMirror graphical user interface (GUI) wizard, you cannot configure an alternate node name or a persistent IP for the first node that you added to the cluster. The first node is used to authenticate to the remote environment. It is included in the cluster with a default node label that is assigned to it.
  • The option to authenticate by using an SSH key is not available from the open terminal feature. SSH authentication is now supported only by password.
  • Due to current technical limitation, a root login is required for restoring cluster snapshots. We will work to remove this limitation in the future.
  • It is not required to install the GUI server inside a PowerHA cluster, although the same is not true for the agent, which must be installed in a cluster.
  • When migrating, after PowerHA SystemMirror installation on Linux, the RSCT will not be started automatically. You must bring cluster online from the backend using the clmgr online cluster command so that the cluster configuration can be managed from GUI server.

Additional information

Documentation

To view the latest version of the release notes, see the PowerHA SystemMirror Version 7.2.2 for Linux Release Notes® topic.

To view the documentation in the PDF format, see the PowerHA SystemMirror Version 7.2.2 for Linux Release Notes PDFs topic.

Man pages

The man pages for the PowerHA SystemMirror Version 7.2.2 for Linux commands are installed in the /usr/share/man/man1 directory. To view the man pages, from the command line, enter man command_name where command_name is the name of the command.

You can use the clmgr command command to perform most of the PowerHA SystemMirror Version 7.2.2 for Linux operations.

PowerHA SystemMirror graphical user interface (GUI)

  • If you configured a cluster to change the host name when an application moves, issues can occur with the PowerHA SystemMirror GUI. You must update the /etc/hosts file for the PowerHA SystemMirror GUI to automatically identify the changed host name. The PowerHA SystemMirror GUI cannot identify temporary host name changes.
  • When you add a cluster to the PowerHA SystemMirror GUI, verify that SSH is not prompting for any unexpected input other than the password or passphrase. To verify that SSH is working correctly, run the ssh REMOTE_NODE hostname command, where REMOTE_NODE is the node you are using to add the cluster to the PowerHA SystemMirror GUI. When you run this command, only the password prompt is displayed.
  • To display the current status in thePowerHA SystemMirror GUI, the cluster must notify the PowerHA SystemMirror GUI. All core PowerHA SystemMirror or events are sent to the PowerHA SystemMirror GUI. When the clmgr command changes the configuration the PowerHA SystemMirror GUI is notified.
  • Node modifications are not supported on the Linux operating system.
  • The default port for PowerHA SystemMirror GUI server is 8080. The default port for the PowerHA SystemMirror GUI agent is 8081. You must ensure that your network allows traffic on these ports. For more information about changing the values for the ports, see the Changing ports in PowerHA SystemMirror GUI topic.
  • You can use only one PowerHA SystemMirror GUI server to manage your clusters.
  • If you install the PowerHA SystemMirror GUI server within a cluster, you must install it on only one of the nodes in the cluster unless you are configuring the PowerHA SystemMirror GUI for high availability. For more information, see the Configuring the GUI to be highly available topic

  • By default the PowerHA SystemMirror GUI server uses the IP address that is associated with the default host name. The PowerHA SystemMirror GUI agents use IP address to communicate cluster status. If you want to use an alternative IP address for the PowerHA SystemMirror GUI communication, specify the IP address in the serverAddress property in the /usr/es/sbin/cluster/ui/server/configuration-server.json. The specified IP address is only used for clusters that are added to the PowerHA SystemMirror GUI after you add the IP address in the serverAddress property. If PowerHA SystemMirror GUI is already managing clusters and you want the clusters to switch to the new IP address, you can rediscover the clusters or manually edit the IP address in the ServerURI property in agent configuration file usr/es/sbin/cluster/ui/agent/configurationagent.json. You must restart the PowerHA SystemMirror GUI server or the PowerHA SystemMirror GUIagent by running the systemctl stop and systemctl start commands.