===================================================================== Release Notes for PowerHA SystemMirror for AIX Version 7.1.3 ===================================================================== These Release Notes contain the latest information about the PowerHA SystemMirror Standard Edition software. There are additional Release Notes in the file release_notes_xd that contain the latest information about the PowerHA SystemMirror Enterprise Edition software. These release notes discuss: o Introduction and naming convention o Enhancements and new features included in this release o Installation and migration considerations o Software prerequisites o Configuration limitations o Notes on functionality o Documentation o Product man pages o Accessing IBM on the web o Feedback The file /usr/es/sbin/cluster/README7.1.3.UPDATE will also be updated by future Service Packs and will contain additional information about any updates. ================================================================== Introduction ================================================================== The 7.1.3 Technology Level of PowerHA SystemMirror builds on the technology introduced with the 7.1 of the product. The 7.1.3 TL also supports the extended distance data replication solutions integrated with the Enterprise Edition version of the software. There is also a corresponding update to the PowerHA SystemMirror Director plugin for this release. ====================================================== Enhancements and new features included in this release ====================================================== o Version 7.1.3 offers a Standard Edition and Enterprise Edition. The Enterprise Edition provides for Disaster Recovery solutions with both host based mirroring and storage based mirroring for data replication. o HyperSwap support has been enhanced to include active=active and single node cluster configurations. HyperSwap with DS8800 storage subsystem provides for continuous availability against storage failures. o CAA now supports unicast for cluster communications and heartbeat. Unicast is the default when configuring new clusters. o The hostname of a cluster node can now be changed dynamically o Additional options are available when configuring split and merge policies in a cluster using sites. o The clmgr command line API has been enhanced with new options and facilities, as well as fully indexed help, cluster copying and html reports. o Enhancements to the Director plugin to facilitate the use of these new features. See the release_notes_assist, release_notes_xd and WhatsNewInThisRelease files for additional information. ========================================= Installation and Migration Considerations ========================================= For prerequisites, and details of install and migration, please refer to the following documentation web page http://pic.dhe.ibm.com/infocenter/aix/v7r1/index.jsp?topic=/com.ibm.aix.powerha.insgd/ha/ha_install_upgrade_cluster.htm For more information about offline migration, see http://pic.dhe.ibm.com/infocenter/aix/v7r1/index.jsp?topic=/com.ibm.aix.powerha.insgd/ha_install_upgrade_offline.htm For more information about snapshot migration, see http://pic.dhe.ibm.com/infocenter/aix/v7r1/index.jsp?topic=/com.ibm.aix.powerha.insgd/ha_install_upgrade_snapshot.htm For more information about rolling migration, see http://pic.dhe.ibm.com/infocenter/aix/v7r1/index.jsp?topic=/com.ibm.aix.powerha.insgd/ha_install_rolling_migration.htm o PowerHA SystemMirror requires an update to the AIX operating system. Updating to a newer TL of AIX typically requires a system outage so you must factor this in to your migration planning. o Using the clmigcheck command A migration assistance tool called clmigcheck is shipped in AIX to aid in the migration planning and process. Note that you need to use this tool only when you are migrating from PowerHA 6.1. When migrating from PowerHA 6.1, update the AIX level on the node to the level required for 7.1.3 (see requisite software section), then use clmigcheck to evaluate the cluster configuration and plan for the migration. Note that you will not be able to install the new version of SystemMirror until you have sucessfully completed the clmigcheck process. o Snapshot migration is supported from version 6.1 and higher. o Rolling migration is supported from version 6.1, 7.1.1 and 7.1.2 o If you do a fresh overwrite install of AIX on a node which is part of an existing SystemMirror cluster, you must take some steps before the node can be rejoined to the cluster: o Make sure /etc/cluster/rhosts is populated with the same entries as the other cluster nodes o Update the repository information using chdev. 1) from another cluster node, find the UUID of the repository in the second field of the output from this command: lsattr -E -l cluster0 -a clvdisk for example clvdisk 96f4b8f5-0321-da43-1333-7112d0651ca5 Cluster repository disk identifier True 2) update the repository on the newly installed node using the chdev command and the UUID from the output above, e.g. chdev -l cluster0 -a clvdisk=96f4b8f5-0321-da43-1333-7112d0651ca5 o Populate the SystemMirror configuration by running Cluster Verification and Synchronization from any other cluster node. o Special notes for migrating from SystemMirror version 7.1.0.0 and CAA version 6.1.6 (2010) If you are not migrating from either of these versions you can skip the next 2 bullets. o Rolling migration is not supported from SystemMirror version 7.1.0.0 to any other version. A full cluster outage is required to migrate from SystemMirror version 7.1.0.0 to any other version. See APAR IV08162 for AIX 6100-07 and AIX 7100-01 for more details on the migration restrictions in AIX. o Manual procedure required when migrating from CAA version 6.1.6 (2010) If you are migrating from a prior release of SystemMirror, and you had been using version 6.1.6 of CAA (bos.cluster.rte) there is an additional manual step required to preserve the pvid of the repository disk in the SystemMirror cluster configuration. Background: One of the steps for migrating from CAA 6.1.6 (regardless of the version of SystemMirror in use) is to remove the CAA cluster definition. This early version of CAA will remove the repository disk pvid when the CAA cluster definition is removed, therefore the repository disk PVID stored in the SystemMirror odm will no longer match the disk that had been used as a repository. Specific tasks for this procedure are documented with APAR IV29501 and you are encouraged to retrieve that information for the most recent updates to the procedure. ============================================== Software prerequisites ============================================== PowerHA SystemMirror v7 is supported on AIX V6.1 and AIX V7.1 Operating Systems. The specific software requirements for PowerHA SystemMirror V7.1.3 are as follows: o Software Levels Required: - AIX and CAA: AIX 6.1 Technology Level 9 with Service Pack 1 or AIX 7.1 Technology Level 3 with Service Pack 1 - RSCT: RSCT 3.1.5.0 with Service Pack 1 The IBM Systems Director plugin for PowerHA SystemMirror version 7.1.3 has been certified with IBM Systems Director version 6.3.3. IBM strongly recommends that you retrieve and install all available Service Packs for SystemMirror, AIX, RSCT and Director (if applicable). IBM Fix Central is available at http://www.ibm.com/support/fixcentral/ ============================================== Configuration Limitations ============================================== PowerHA SystemMirror is a flexible and extensible solution for your high availability needs. You can configure any size cluster up to: Maximum nodes per cluster: 16 Maximum resource groups: 64 ====================== Notes on Functionality ====================== This section contains notes on known limitations. Please also refer to the file /usr/es/sbin/cluster/README7.1.3.UPDATE for additional updates as new service packs become available. o /etc/cluster/rhosts must be populated with all cluster IP addresses prior to using v7 PowerHA SystemMirror. This was done automatically in prior releases but is now a required, manual process. The addresses you enter in this file must include the addresses that resolve to the hostname of the cluster nodes. If you update this file you must refresh the clcomd subsystem with "refresh -s clcomd" o You can choose between unicast and multicast for cluster communications and heartbeat. If you select multicast, you must enable your networking infrastructure to allow multicast traffic. Use the mping command to verify multicast communication works between the nodes that will be part of the cluster. Refer to the documentation from the switch vendor to enable the multicast communication through the switch if necessary. Note that this may be necessary if there cascaded switch configured in the environment. Many switches turn off the routing of multicast packets by default. o The cluster repository disk must be no smaller than 512MB and no larger than 460 GB. o Dynamically changing Universal ID's (UID and UUID) is not supported. These ID's are normally invariant under most circumstances, though there are known scenarios - like re-installing the operating system - where they will change. If you make any such changes you will need to remove the CAA cluster first to ensure all IDs are updated. For example, if you change a node name in SystemMirror, you must remove the CAA cluster before using Verification and Synchronization to update the new node name. o The resource group option "Automatically Import Volume Groups" is no longer necessary. To update the volume group information at any time you can use CSPOC: smitty cspoc -> Volume Groups -> Synchronize a Volume Group Definition o User supplied Dynamic Node Priority cannot be used when sites are defined in the cluster. o The cluster test tool (CTT) uses AIX facilities to simulate interface failures. These facilities do not simulate failures to CAA, which uses a very low-level access to the interface. This means that the default CTT programs may not provide realistic test of network events. IBM plans to remove this restriction in a future release. o Users of the IBM Systems Director plug-in may see a message "Problem handling a request". If this occurs please close the Tab and try the function again. o The PowerHA SystemMirror Director agent plug-in version 7.1.3 can only communicate with an IBM Systems Director server where a 7.1.3 or later version of the PowerHA SystemMirror server plug-in is installed. o See the file release_notes_assist for additional information on Smart Assists. o When IPv6 is configured in the cluster, autoconf6 will be run for each interface with an IPv6 address configured. By default, autoconf6 will create LL addresses starting with FE80. However, if you have configured ndpd-host daemon to listen for a router advertised prefix in the network, then a global IPv6 address may be assigned which can have a network address starting with 2xxx. PowerHA SystemMirror will not recognize these addresses as being LL. This particular combination is not supported. o The CAA cluster is created when the SystemMirror cluster is synchronized. If the CAA cluster is created with the multicast option for cluster communications, it will begin sending multicast packets on the network. The mping facility relies on sending and receiving multicast packets from specific addresses. If CAA is using a specific multicast address, and mping is run - either from cluster verification or from the command line - mping may detect multicast packets that were generated by CAA. Warning messages from mping should be investigated, but may not be actual errors when seen in an active CAA cluster. The statistics printed when mping completes should guide the decision regarding the health of the network. o The PVID of a repository disk may change once the CAA repository is created on the disk. This can happen if the VGDA area of the disk is corrupted prior to the creation of the CAA repository volume group: the LVM will assign a new PVID if it is unable to process the current data in the VGDA. You can avoid this by selecting only valid disks when chosing the CAA repository. o When configuring a tiebreaker disk for split and merge recovery handling, the disk must also be supported by the AIX devsrc command. The smit picklist for selecting the tiebreaker disk will filter out any disks that do not meet this requirement. Note that EMC disks currently do not meet this requirement. o Uninstalling the SystemMirror software will not remove the underlying CAA cluster definition. If you intend to permanently remove SystemMirror from your cluster nodes, you will need to manually remove the CAA cluster definition using: CAA_FORCE_ENABLED=1 rmcluster -f -n or CAA_FORCE_ENABLED=1 rmcluster -f -r =================================== Documentation =================================== IBM no longer uses form numbers for documentation. The books available for PowerHA SystemMirror are listed here. PDF and html versions are available online at http://pic.dhe.ibm.com/infocenter/aix/v7r1/index.jsp o PowerHA SystemMirror concepts o Planning PowerHA SystemMirror o Installing PowerHA SystemMirror o Administering PowerHA SystemMirror o Troubleshooting PowerHA SystemMirror o Programming client applications for PowerHA SystemMirror o PowerHA SystemMirror for IBM Systems Director o Smart Assists for PowerHA SystemMirror Note that all the smart assist documentation is combined into a single book. o Developing Smart Assist applications for PowerHA SystemMirror o Storage Based High Availability and Disaster Recovery o Geographic Logical Volume Manager ------------------------------------------------------ Viewing and installing the documentation files ------------------------------------------------------ You can view the PDF documentation without installing the product. Simply copy the PDFs from the installation media to your desired location or view them directly from the media. If you prefer you can install the documentation by installing the cluster.doc.en_US.es.pdf fileset. The Smart Assist book can be installed with the cluster.doc.en_US.assist fileset. Note: Installing all of the documentation requires about 8 MB of space in the /usr filesystem. The documentation (pdf files) is installed in the following directory: /usr/share/man/info/en_US/cluster/HAES ================== Product Man Pages ================== Man pages for PowerHA SystemMirror commands and utilities are provided with the cluster.man.en_US.es.data and are installed in the following directory: /usr/share/man/cat1 Use man [command-name] to access the man page. ======================== Accessing IBM on the Web ======================== o Access IBM's home page at: http://www.ibm.com PowerHA SystemMirror main page: http://www.ibm.com/systems/power/software/availability/aix/index.html Downloading the Systems Director plugin: http://www.ibm.com/systems/software/director/downloads/index.html IBM publishes Redbooks for a wide range of topics including PowerHA SystemMirror - visit http://www.redbooks.ibm.com PowerHA SystemMirror v7 Redbook: SG248030 http://www.redbooks.ibm.com/redpieces/abstracts/sg248030.html?Open ======== Feedback ======== IBM welcomes your comments. You can send comments and questions via e-mail to: hafeedbk@us.ibm.com