In today’s highly security-conscious network environment, it’s important that you be aware of some of the common security exposures that could lead to a security breach of your systems. Even though there are excellent security features built into IBM i, today’s network environments often open your systems to exposures not even dreamed of a few years ago.

Based on numerous security reviews I have conducted across different industries, the same types of security exposures appear over and over again. In this series of articles, I describe the top 10 most common security exposures and provide suggestions for minimizing your risk.

Like most people who use SQL, I have never bothered worrying about which case a field name is written in. Case never seemed to matter. However, while performing a data fix, I discovered an instance where it does. (Fortunately, I was using test data!)

I had a number of files from which records were to be deleted. The key values of the records to be deleted were held in a spreadsheet. There were three fields, one of them called VERSION, in the files I was deleting from.

I tried to create a table to store the contents of the spreadsheet,

A reader recently wrote asking how to configure i5/OS to use TCP/IP communications while in restricted state. Here are my prototype instructions for accomplishing this task. Due to constant uptime demands on my machines, however, I haven’t yet been able to fully test this process. But I invite any interested readers to test these instructions and write in with suggested changes. I’ll publish the best comments in a future article.

Getting Started with Restricted State TCP/IP

If you’re running recent versions of i5/OS or the i operating system, you should be able to run a subset of TCP/IP functions in

In Subprocedure Return Values–Food for Thought, I discussed the performance implications of returning large variables from subprocedures. With IBM i 7.1, IBM has added new RPG compiler features that improve performance when passing large parameters.

The conclusion of my previous tip was that you should use a conventional parameter–instead of returning a value–when large values such as result sets were involved. The downside of such a change of course is that you lose the ability to know exactly which field was changed by a procedure call. Seeing:

	GetCustomers( state: customerList ); 

in the code just doesn’t make what is

Everybody knows that the Work with Links (WRKLNK) command lists all the files (including subdirectory entries) in an IFS directory, right? Well, to quote Ira Gershwin, it ain’t necessarily so. Your system may have IFS files that you don’t know about.

One of the UNIX conventions that the IFS has inherited is that files whose names begin with a period (“dot”) are considered to be hidden. By default, their names are omitted in directory listings. Hidden files are commonly used for system files, configuration files, and temporary files. But there’s nothing to stop other people from beginning file names with

We just activated passphrase support on our i5/OS V5R4M5 system. After activation, one of my Web server ODBC connections stopped working and I have no clue how to reset it. How can I get it working again?

–Keith

After getting this email, I contacted Keith and ran through a few scenarios. Here’s how we solved this issue as well as another issue that was hiding right behind it.

First, we found that Keith was using an embedded password for his ODBC connection, which resided on a Web server that was automatically updating i5/OS data. The password was set to “LETMEIN”