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Intrusion Prevention and Active Response

The more security books I read, the more I feel like I'm standing in a hall of mirrors, with the villian plainly visible pointing a weapon at me. But where is he? Which reflection is the one I need to pay attention to?



Title Last Comment
Some UNIX tools I love  
- Without the clean design and power of UNIX OS, there could not have been the ecosystem and the atmosphere for programs that do great things. -

Digiboard Port Server changes tty device permissions  
- Earlier this week, one of those customers called with a problem of changing perms on his /dev/tty* devices. He needs them set with write permission (666), but some were seemingly randomly resetting to 600. -

Mplayer on UNIX and VLC on Windows   2011/10/19 anonymous
- Mplayer for Unix/Linux media playing. Both play multimedia files - both audio and video. But the approach taken towards solving this problem is quite different. -

Simulate complex networks with qemu  
- Every qemu instance forms part of the host bridge and it will behave exactly like a computer attached to your switch/bridge. -

Network Troubleshooting   2010/03/16 AndrewSmallshaw
- As it turned out, the problem was very physical: a light fixture had fallen down and loosened some connections to a long forgotten ethernet switch. -

What does a leading colon (:) mean in a script?  
- Bash and sh use colons as a separator ($PATH, for example), as a modifier (${n:="foo"}) and as a null operator ("while :"). -

Hylafax on Centos Scripts  
- Aside from transferring user accounts, printers, and so on, my work was just to convert Vsifax scripts to Hylafax. Those scripts were called by the application program to do such things as fax a Purchase Order to a vendor. The programming is simple enough: you find and extract the fax number and pass that all off to Hylafax. For purposes of logging and error control, we also wanted to identify the vendor name, which required adding that name to the logs that Hylafax keeps or maintaining a separate index of names to faxes queued. -

Running old Linux apps on new Distros  
- How to run old Linux apps on new Distros. Sometimes the original app vendor still exists and is willing to be helpful, sometimes they are out of business or uninterested in the old app because they want to sell something newer. -

Basic TrueCrypt Usage   2010/01/12 TonyLawrence
- People have said that they installed TrueCrypt, but have no idea what to do next. OK, maybe the interface isn't all that user friendly. -

Lan sniffing with a DualComm port mirroring switch and Windump   2010/01/23 TonyLawrence
- Using Dualcomm Port Mirroring switch and Windump to trace network problems and detect virus activity. -

Unix and Linux startup scripts, Part 1  
- In the beginning, there was "init". If you had a Unix system, you had "init" and it was almost certainly process id 1. -

Unix and Linux startup scripts, Part 2   2009/12/11 TonyLawrence
- The rc.d system is used on NetBSD, FreeBSD and DragonFly (and possibly a few other systems) to launch daemon processes when the system goes multiuser. -

Unix and Linux startup scripts, Part 3  
- We have looked at both System V and BSD methods; until fairly recently that would hav e been the end of the discussion. -

Why Microsoft should fear Chrome OS, Linux and Apple   2011/04/20 TonyLawrence
- The big question is how Microsoft will fare if Chrome OS and Apple's rumored iTablet (whatever they finally call it) become popular. -

Using color in shell scripts (Linux, Mac OS X)   2010/01/03 BigDumbDInosaur
- Color is tricky. Displays can be bad at it, people can be color blind... using colors can make text hard to read - I don't like using color in scripts. -

Sort -u vs. uniq  
- Don't tie yourself in pipeline knots with either of them; learn to use each of them appropriately and your scripts will be easier. -

Awk vs. Perl   2012/08/15 TonyLawrence
- Sure, I used to use awk. When I used it, you weren't likely to find Perl onmost Unix systems, so for a lot of text mangling, awk was at least easier than writing in C or anything else. It did the job, and you'd get used to its quirks. -

Hylafax 6 on Centos 5   2010/01/26 bubba
- I'm doing another SCO to Linux conversion and this one used Vsifax. That's hardly a show stopper, but this customer wanted to use Centos and Vsifax says they don't currently support using Centos. So we tried Hylafax. -

Fishing for an unknown device  
- If you have a DHCP server anywhere in the network, the device will have obtained an IP address. But what is it? -

 
 
Kerio Connect Mailserver
 
 
Chrome OS on Vmware Fusion  
- A look at Chrome OS in VmWare - basically, this is Linux in kiosk mode - the only apparent app is the browser. -

Freeing disk space with >  
- I wrote this up after a forum discussion in which several posters didn't really understand why '>' can free disk space when 'rm' cannot. -

New Comment Policy   2009/12/18 francois
- We had to switch to partially moderaed comments here because of some really nasty people. Gosh I hated doing that! -

Fear and Loathing of Chrome OS?   2009/12/23 TonyLawrence
- I can understand some people feeling threatened and that there is a definite loss of control when moving away from our traditional paradigms. -

Google's Go  
- Normally, the announcement of a new language isn't likely to get me to even click through to read about it but Google go is worth looking at. -

A strangely compromised Linux box  
- A customer reported that a Linux machine used for ssh access (to in turn give telnet access to an ancient SCO machine) was refusing logins. -

When Samba Pigs Fly  
- Yesterday a customer called because he needed to be able to write into a certain share on his Samba shares. -

The cure for everything - chmod 777  
- I admit that I have done a chmod 777 when I should not have. -

Prevent deletion or moving of files  
- You need to let users create files in a common directory, but you don't want them to be able to delete other's files. Or you've put certain files, directories or symlinks into a user's home directory and don't want them to be able to mess with any of those. What can you do? -

Create syntax highlighted PDF and HTML files from C or perl  
- Create syntax highlighted PDF and HTML files from C or perl -

Plenty of space here  
- Like many people, my customer doesn't understand spaces in command lines. Unlike most, he's not one to leave spaces out - no, he's more likely to insert gratuitous spaces where none are wanted. -

Follow the bouncing dependencies  
- Now, given that I installed RHEL 5.3 from rpms, and did notcompile my own kernel, I figured that I would be missing some packages,but it turned into a major pain. -

Is Linux the One True Religion?   2013/06/24 TonyLawrence
- There is only one true religion, though it's impossible to know whether it's Linuxism, BSDism or SysVism -

Network Know-How  
- This is the book I'd give to someone who needed to learn a lot about computer networks, quickly. -

Vim: edit with vim  
- For people who hate vi, vim does not offer much relief. -

How do I set up a network printer or print server?   2010/06/23 TonyLawrence
- How do I set up a network printer or print server? -

A primer on networking and routing topologies  
- We are going to look at how you can setup your home or office Linux box to do simple packet forwarding with static routes. -

X hotkeys with xbindkeys  
- xbindkeys is very easy to use when you wish to bind hotkey presses on X sessions -

How to use multiple consoles in Single User mode   2012/09/16 TonyLawrence
- You don't have to e limited to one console in single user mode. How to get more does vary among distros, but is not difficult. -

Facetwin logs wrong ownership  
- Facetwin writes a message to /usr/adm/syslog every time it finds a file in my /1/users/prog that has ownership other than prog! -

How do I capture program screens to a file or print them?   2012/09/17 TonyLawrence
- Various ways to capture text or screens on Unix/Linux and Mac OS X and Windows. -

Creating pretty graphs with RRDTOOL   2014/09/03 Varun
- The open source rrdtool project helps you create a graphical view of any statistic collected at regular intervals. -

The amazing tool called netcat  
- netcat with its simple and yet incredibly powerful command line constructs has helped me innumerable times -

Protect your Laptop with TrueCrypt  
- Truly affordable hard drive, laptop and USB Drive encryption software for your business critical data -

Concepts in Cryptography  
- Basic cryptography has wide application. Understanding the basic concepts isn't difficult. -

A Gentle Reminder About Backup  
- This will backup to just about anything - tape, cd, dvd, NAS, ftp sites. -

An Unexpected IP  
- Windows, Linux, Mac OS X, it would have all been the same: An old server had an OS transplant and needed to be connected to the network. -

Yet another article on open source  
- Why you might want to open-source your software project or application - multifaced benefits. -

Some fun tools in the UNIX ecosystem  
- Some fun tools in the UNIX ecosystem include 'randtype', which pretends to be a human typist. -

Creating screencast video tutorials for the web   2012/07/06 TonyLawrence
- Basic Linux video: Creating video tutorials is a novel method of web based tutoring. Nowadays right from product demos for marketing/sales to technical talks, everything is found in youtube. Videos are a powerful medium to get your idea across and your audience can quickly understand what you are trying to convey when they see a video. -

Windows Spam on Linux  
- There were some .wine files in our /tmp, which would explain the Windoze-like appearance -

 
 
Kerio Control Firewall
 
 
How to become a hacker  
- Not only in programming, be it any activity. Unless one loves -

Security vs. Convenience  
- Sure, if you want to completely destroy your security -

Opera Unite is a little Wave  
- Opera's servers access your content and share it with others. -

The Helios Project  
- Building Linux computers for disadvantaged children -

Centos ssh failure  
- I have a customer who uses a fairly new Centos server to function as an ssh gateway to his ancient SCO box. On Friday he told me that no one could ssh in. -

Firefox 3.5 out soon  
- Can't live with it, can't live without it this is an old review and is only here for historical purpose. -

Fear of fsck   2011/06/02 KenPorter
- They were afraid to run fsck for several months - were their fears justified or were they being foolish? -

Another SCO box  
- The hardware is five years old, it's time to dump SCO and move to Linux. -

Ubuntu on a Toshiba Satellite   2010/12/31 anonymous
- I installed Ubuntu 9.0.4 on an old Toshiba Satellite Laptop last night - the owner will probably take it off later, but for the moment he is a Linux user! -



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