Edit: Some links no longer work.
Originally posted October 9, 2012 on AIXchange
I don’t know who at IBM developerWorks wrote this document, but I really like it. By following along with the sections as outlined, you’ll learn how to define and configure PowerHA SystemMirror for AIX.
The first section includes references to a good introductory article, while section two focuses on infrastructure planning and configuration and section three has an IBM Information Center document on smart assists. The final three sections cover networks, resources and resource groups, creating a cluster and testing a configured cluster. Finally, there’s a cheat sheet from Christian Pruett and information about PowerHA training.
Information from the opening chapters of this Redbook is noted throughout the document, plus there are links to presentations, including a couple from IBMer Alex Abderrazag. I appreciate the inclusion of training information and really like how the document is organized overall.
Here’s another resource for PowerHA users: the new IBM draft Redbook, “IBM PowerHA SystemMirror Standard Edition 7.1.1 for AIX Update.” This was just released in September.
Just a quick point about SystemMirror: It runs a feature under the covers called cluster-aware AIX, which is integral to managing shared stored pools in VIOS. I’ll write more about this soon.
As for the SystemMirror Redbook itself, one thing that stands out to me is the step by step instructions for setting up a cluster in Chapter 3. There’s also this, which, quite honestly, made me chuckle:
“During the developing of this book, the repeating question was: what is the recommended virtual Ethernet configuration? The authors all had their own opinion, and there were many long debates on this topic. Finally we agreed that there is no specific or recommended virtual Ethernet configuration because all redundant configurations should work well in a PowerHA environment.”
To me this paragraph nicely sums up our profession. We all have strong beliefs about how to configure systems, and we’re often pretty vocal in pointing out the distinct advantages of our own particular way of doing things.
And it turns out that, despite their disclaimer, the authors managed to get together and settle on these recommendations for configuring virtual Ethernet:
* “Two Virtual IO servers per physical server.
* Use the servers’ already configured Virtual Ethernet settings because no special modification is required. In case of a VLAN tagged network, the preferred solution is to use SEA failover, otherwise use the network interface backup.
* One client side virtual Ethernet interface simplifies the configuration; however, PowerHA misses network events. (This can be remedied by applying APAR IV14422 and configuring your /usr/es/sbin/cluster/netmon.cf file as described in section 3.8.2)
* Two virtual Ethernet interfaces on the cluster LPAR because this enables PowerHA to receive the network events. This results in a more stable cluster.”
I do encourage you to check out all of these resources. With freely available information like this, learning about building a PowerHA cluster is easier than ever.
Reminder: IBM had a big announcement last week featuring POWER7+ hardware and software. I covered the many new solutions and features in this special post.