Configuring Cluster Notifications

Edit: Link no longer works.

Originally posted December 10, 2012 on AIXchange

A customer running a PowerHA 7.1.1.2 cluster wanted to be notified when nodes were down and when the resource group moved in their cluster.

Check here and you’ll find details about configuring a custom remote notification method:

“These topics describe how to configure custom remote notification methods to respond to an event, how cluster verification confirms the remote notification configuration, and how node failure affects the remote notification method.

“You can configure a remote notification method through SMIT to issue a customized numeric or alphanumeric page in response to a specified cluster event. You can also send SMS text message notifications to any address, including a cell phone SMS address or mail to an email address. The pager message is sent through the attached dialer modem. Cell phone text messages are sent through email using the TCP/IP connection or an attached GSM wireless modem.

“You can send the following custom remote notifications:

  • Numeric and alphanumeric page
  • SMS text message to any address including a cell phone or mail to an email address
  • SMS text message using a GSM modem to transmit the notification through a wireless connection

“The PowerHA SystemMirror remote notification functionality requirements follow:

  • A tty port used for paging cannot also be used for heartbeat traffic
  • Any tty port specified must be defined to AIX and must be available
  • Each node that might send a page or text messages must have an appropriate modem installed and enabled

“Note: PowerHA SystemMirror checks the availability of the tty port when the notification method is configured and before a page is issued. Modem status is not checked.

“To send an SMS text message over the dialer modem, your pager provider must offer this service.

  • Each node that might send email messages from the SMIT panel using the AIX operating system mail must have a TCP/IP connection to the Internet
  • Each node that might send text messages to a cell phone must have an appropriate Hayes-compatible dialer modem installed and enabled

Each node that might transmit an SMS message wirelessly must have a Falcom-compatible GSM modem installed in the RS232 port with the password disabled. Ensure that the modem connects to the cell phone system.”

My customer just wanted to receive email notifications, but I still had to make sure that I had a tty device defined on the node. I used smitty (smitty sysmirror) to access the PowerHA menus. From there, I selected: Custom Cluster Configuration > Events > Cluster Events > Remote Notification Methods.

I had to select the Configure a Node/Port Pair option. Defining a port would make sense if I was connected to a modem, but it was a needless endeavor in this case, since, as noted, my customer was only interested in enabling email notifications. Hopefully node/port pair configuration will be optional in future PowerHA SystemMirror releases.

In any event, in this screen I chose the node and port. Then I selected the Add a Custom Remote Notification Method option. In these fields I entered a name and the nodenames in the cluster. In the Number to Dial field I entered the email address that would receive the notifications. Then I chose the cluster events for which notifications were desired: rg_move, node_up and node_down. PowerHA users can choose numerous other events, however.

Once it was set up, I verified and synchronized the cluster. Then I ran the Send a Test Remote Notification menu option to make sure it worked. It did.

While I could have done pre- and post-event commands along with some scripting, I felt that using the remote notification method was the better way to go.

The final test came once the cluster was running. We moved the resource group from one node to the other. The notification worked as expected and we got the email notification we wanted.

Have you set up something like this in your HA environment?