Tuesday, November 17, 2009

SQLite Database

If you have been using CSV/flat file as a persistent storage for your scripts, you should really checkout, SQLite. It gives you the power of RDBMS while without the complexity that comes with it. Any SQLite database you create is nothing but a file. It provides locking, transaction support, joins, etc. With ".dump" command, it can generate the SQL commands to reproduce the whole schema.

Did I mention, this database format is supported by ActivePerl, by default? You can use the standard Perl DBI module to manage this database.

Also, there is a CLI tool called sqlite3 (~500K) that lets you run all database manipulation and SQL commands. And, if it is good enough for Google Android and Apple Safari, chances are it should be robust enough for my needs.

Here is a simple Perl script to access this database from Perl.


use DBI;

my $dbh = DBI->connect('dbi:SQLite:dbname=sample.db',',');

$sql = qq{ CREATE TABLE MYCERT ( num int not null, name varchar(20) ); };
$sql = qq{ INSERT INTO MYCERT VALUES(1, 'ITM'); };
$sql = qq{ INSERT INTO MYCERT VALUES(2, 'Omnibus'); };


Thursday, November 5, 2009

To AB, or not to AB

If you are looking to develop custom monitoring solution in ITM, ITM gives you two options, viz. an eclipse GUI based Agent Builder tool or Universal Agent (UA). Which one would you choose? While the agent builder is shiny and easy to use, UA solution has its own advantages. Read on to know some of the pros and cons of each approach.

Agent Builder based solution makes sense for the following scenarios.

1) If you want to deploy something real quick and easy, then Agent Builder is a good candidate for your needs. Once you are familiar with the agent builder interface, you can create a custom monitoring agent literally in minutes. Moreover, there are not many typos/mistakes you can make with the Agent Builder's GUI based approach.

2) If you generally prefer GUI method over CLI methods, you will like Agent Builder more.

3) If you want to pull from data sources such as JDBC, WMI, NT Event Log, Service Control Manager, etc, then you should be build an agent builder agent with few clicks. UA will require lot of work as you may have write your own code to pull data from these data sources.

4) If you want to integrate the custom monitoring deployement with your current agent deployment methods, then obviously agent builder is the way to go. Deploying agent builder is very much the same as deploying any other agent.

Universal Agent based solution makes sense for the following scenarios.

1) If you want to minimize the number of agents you want to manage, then you are better of with UA. For example, if your requirement is to deploy 'n' custom monitoring solutions, typically agent builder would require 'n' agents, whereas in case of UA, one agent should be able to perform all 'n' monitoring activities.

2) Let me prefix this statement with a caveat. Check with your IBM representative for all licensing related information. Since one UA can handle multiple monitoring tasks, the licensing costs of UA based solution is typically lower than that of Agent Builder.

3) If you have been using UA for a long time, you can deploy the UA solution as quickly as an Agent Builder solution. More over, UA works pretty reliably.

4) If your monitoring requirements needs advanced summarization capabilities, then UA provides more advanced features than agent builder. Again, some of these tasks can be done using by modifying the itm_agent_toolkit.xml file, but it is just that the Agent Builder capabilities in this regard is not fully known yet.

Hope this information is helpful in your next custom monitor deployment.