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So far Tony Lawrence has created 47 blog entries.

BackupEDGE 2.1

2010-05-26T11:24:43+00:00 May 3rd, 2005|Linux|

The latest version of Microlite BackupEDGE adds several new features. For those who are not familiar with the product at all, a quick recap is in order:

Magic Sysrq

2010-05-26T11:24:36+00:00 May 3rd, 2005|Linux|

The Magic Sysrequest Key is Alt (left or right Alt key) and Sysrq (up there under Print Screen, next to F12 on most keyboards). To use it, you need to have it enabled in your kernel (CONFIG_MAGIC_SYSRQ). It usually is; if you have a file called '/proc/sys/kernel/sysrq' you have this. To ENABLE the magic functions, you need a 1 in that file. If it has 0, Alt-SysRq just returns you to the previous console you were using.

Blacklist Unwanted IP Addresses

2010-05-26T11:24:23+00:00 May 3rd, 2005|Linux|

On Linux, it's easy enough to add an iptables rule to blacklist a particular ip address. You can even automate the process based on certain criteria that you define. However, you don't necessarily want to leave an ip blacklisted forever, because it may be transient (a legitimate user may have that ip address tomorrow), or the condition that triggered your block may have been an error. The ip address may even have been spoofed, thus denying access to legitimate users.

Transferring Mail to a New Mail Server

2010-05-26T11:24:10+00:00 May 3rd, 2005|CGI and Perl|

Sometimes we just have to move on. Your current mail server may just not be meeting your needs, so you've put up something new. But what about old mail? If your servers are identical (Sendmail to Sendmail, etc.) or use the same mailbox storage format, you may be able to just transfer files directly. If not, read on..

Web Log Analysis

2010-05-26T11:25:46+00:00 April 30th, 2005|CGI and Perl|

There are many tools available to analyze web page statistics. One of the most popular is Analog, but any web search will turn up hundreds or perhaps even thousands more. There are also options like Hitbox which provides statistics gained through code included in your web pages.

Perl Net::FTP

2010-05-26T11:26:48+00:00 April 27th, 2005|CGI and Perl|

Before the wide spread availability of Perl, I would script ftp transfers with .netrc, ksh scripts and other clumsy ways. None of those methods are fun, flexible or easy. On the other hand, Perl's Net::FTP module is all of that.

Fork and Exec with Perl

2010-05-26T11:27:46+00:00 April 27th, 2005|CGI and Perl|

Recently I had a project that required a number of different programs that will mostly run all the time, but need to be restarted now and then with different parameters. Normally, the first thing I think of for a program that runs constantly is inittab or svc (daemontools). The svc facility is the more flexible of the two, and will be what I'll use in the final design, but in the "thinking" stages I played with using a Perl program launcher and controller. What we have is a config file that specifies programs

Text Configuration Files and XML

2010-05-26T11:28:25+00:00 April 25th, 2005|XML|

Configuration files are a problem for both operating systems and applications. Where do you keep them, how are they structured? Traditionally, Unix systems used text files with wildly varying internal structures, and Windows used either binary data or ".ini" text files (in this sense, "binary" is used for anything that you can't access directly with a simple text editor). More recently, Windows abandoned .ini files in favor of a binary central registry.