Nothing much, just a script to walk the tree for a given name. It starts at a CNAME and walks its way all the way down to the A record and IP address. In the context of larger script that…
Author: Steve
Query HBase from Tomcat
We installed Tomcat 6.0.39 (we weren’t running JDK 1.7), as well as hbase. To get this to work, we copied the following jar’s from the hadoop and hbase installation directories to the tomcat lib directory. -rw-r–r– 1 serengeti serengeti 5212641…
Automated Weblogic versioned app deployment
We had a need to automate deployments with a versioned app. You can place an entry in the MANIFEST.MF for “Weblogic-Application-Version: v14”, or whatever, or you can dynamically assign it at deployment time. What is below will do the latter…
Monty Hall simulation in python
The Monty Hall problem, or paradox as it is sometimes known, has always intrigued me, so much so that I wrote a python based simulator to prove it to be true or false. The crux of it, and as its…
Weblogic WLST – Accessing OS variables
As with all thing wlst, almost everything you can do in python you can do in wlst. Below is just a simple example of accessing host variables from inside of weblogic. [sa-weblogic@cmhldecomadm01 Middleware]$ export FOO=”BAR” [sa-weblogic@cmhldecomadm01 Middleware]$ ./Oracle_Home/oracle_common/common/bin/wlst.sh Initializing WebLogic…
Why isn’t my cursor being shared?
This is a decent way to determine why a cursor isn’t being shared, resulting in cache locking during parsing (134 minutes total yesterday, which is very high historically)… SQL> select count(*),sql_id from gv$active_session_history where event = ‘library cache lock’ group…
Using Apache POI to generate Excel spreadsheets from database queries
Back in the 90’s when I first started working with computers professionally, I remember finding software for $49.95, and often much more, to do on Microsoft Windows what is now free. Apache POI (“Poor Obfuscation Implementation” 🙂 ) is a…
Installing a specific kernel related package without upgrading the kernel
If you simply type “yum install package_name”, you will get the most recent version available in the package repository to which you are pointing. If this is a kernel related package, you can inadvertently upgrade the kernel, which may be…
HAProxy setup
I wanted to have a deeper understanding of load balancing. I tested with several different open source products, but the most recent release of HAProxy (1.5.21) was the easiest to get running. I wanted to test the following on RHEL…
Using strace to determine progress when processing a file
I thought this was interesting, as I stumbled upon it. I find the most useful things often result from stumbling 😉 I had a job running that was gunzip’ing a file and piping the output to a python script. The…