Where are the logs for the SCAN listeners?

Quick post and note to self. Where are the SCAN listener log files? A little bit of troubleshooting was required, but I guess I could have read the manuals too. In the end it turned out to be quite simple!

First of all, I needed to find out where on my four node cluster I had a SCAN listener. This is done quite easily by asking Clusterware:

[grid@rac11gr2node2 ~]$ srvctl status scan_listener
SCAN Listener LISTENER_SCAN1 is enabled
SCAN listener LISTENER_SCAN1 is running on node rac11gr2node2
SCAN Listener LISTENER_SCAN2 is enabled
SCAN listener LISTENER_SCAN2 is running on node rac11gr2node4
SCAN Listener LISTENER_SCAN3 is enabled
SCAN listener LISTENER_SCAN3 is running on node rac11gr2node3

I was initially on the first node, so had to ssh to the second. From there on I thought that the proc file system might have the answer.

Change SCAN post installation

A quick note to myself on how to change the SCAN from /etc/hosts to DNS. I have set up a small DNS server for a local interface on my dom0 to help me resolve problems around TAF and session failover in general. This is a test/dev/playground cluster-you should have never been in this situation with anything used “for real”! Multipe IP addresses for a SCAN are needed since you no longer specify all the node VIPs in tnsnams.ora-there is no FAILOVER=yes either! DNS round robin now provides this for you.

Building your own RAC system part III: Grid Infrastructure

This is the third part of my “build your own RAC” article series, and this time we are about to install and discuss Grid Infrastructure.

After all the prerequisistes are met, some of which are described in previous posts, it’s about time to begin with the installation of the Grid Infrastructure. As with the artist Prince, Grid Infrastructure has come with many names – Cluster Ready Services (10.1), Clusterware (10.2 & 11.1) and now finally Grid Infrastructure.

Download the necessary zipfile from OTN as always and unzip it somewhere you like, then execute runInstaller. You will notice that OUI in 11.2 has gone red, and it looks quite different from previous versions. I will attach screenshots of the installation process once I have figured out how that works with my blogging software. Since the Grid Infrastructure installation is quite unlike the previous Clusterware installation I thought I’d point out the differences.

My sample setup has to serve a number of purposes:

• I want to try adding a node to the cluster. Will it really be as simple as they say?
• I want to try RAC One Node – how good will omotion be?
• I am testing Grid Plug And Play.

So if you find anything strange such as all SCAN addresses on a single host, then it’s because I haven’t had time to extend the cluster.