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February 2005

ex: Tech Words of the Day 
- Ex is the non-visual mode of vi, the mode that you are in when you type ':'
Testing new comments system 
- I haven't been happy with our Wiki based comments system for some time.
pointer: Tech Words of the Day 
- all sorts of pointers: indirect pointers, dangling pointers, stack pointers, function pointers, array pointers
Backdoor: Tech Words of the Day 
- A backdoor account is an account that has root privileges. If installed by a hacker, that's obviously a bad thing.
scsidev: SCSI utility for linux   by Bruce Garlock
- I recently built an external SCSI enclosure, using an old tower. I used 3 SCSI drives, and built a LVM, so I could concatenate the drives together into one large drive, to host my temporary video scratch files.
File does not exist error from Microsoftt Save As 
- Microsoft save as produces annoying junk in my error logs. Can those idiots do anything right?
quoted-printable: Tech Words of the Day 
- spammers use this and other encodings to disguise their work
Ethereal: Tech Words of the Day 
- One (of many) interesting features is the ability to reconstruct a tcp session in the order the application would have seen it .
Strange Terminal Emulation problem 
- I could attach an old Wyse60 terminal to the same line and it worked fine no matter what emulation was chosen. With the PC, however, even changing emulation after logging in, with or without a tset, would send the screen insane - looked to me like the baud rate had suddenly changed.
Sendmail Milters 
- With libmilter, sendmail can call other programs to help determine the disposition of a message. There can be multiple external programs, and sendmail makes calls at different points
Virus Research and Defense 
- This book by Symantec's chief researcher should scare you, because the bad guys are winning the virus wars. This book can be heavy geek territory. If you aren't fascinated by the details of executable programs and the like, some of this will be hard sledding. But if you are the type who likes to take things apart to see how they work, this is for you.
stealth firewall,ebtables: Tech Words of the Day 
- A stealth firewall is a bridge that applies firewall rules to packets that pass through it. The reason "stealth" is used is because a bridge is transparent to the machines using it: they can't tell that all the machines in the subnet aren't on the same physical lan. This also means that you can insert and remove such a device without disruption or indeed any awareness by the users of the network. The device itself doesn't even requre any ip addresses of its own, so it can be truly invisible.
Internet Sharing using a Linux box  by amarjyoti
- Since the Internet is a large network composed of smaller networks, it made sense to break the address space into smaller chunks. Network classes enable us to break down this address space.
Samba problems 
- Common samba problems: adding passwords for Windows clients and adding or mapping Windows user names.
REALbasic: Tech Words of the Day 
- You shouldn't necessarily be entirely disdainful, either. Bad code is possible in any language, and so is good code.
Octopus Virus? 
- What is an octopus virus? The description sounds more like a snake to me and I also found an odd definition of 'worm'.
More ssh ideas  by Dirk Hart
- A friend recently got 'rooted'. He was using ssh (not ssh2). He was getting pages on his phone and processes were dying and such, so he installed "chkrootkit" which is a program that checks your system to see if there is any of a number of root kits installed. He had SuckIt installed on his machine and now has a server to rebuild.
Win4LinPro released: Support for Win2K, WinXP  by bruceg
- This product no longer exists. VmWare, Parellels and a few free virtualization products replace it.
Print to FAX with custom tags 
- How to use VSIFAX as the target of a System V printer interface script with custom tags.
Buffer Overflow Attacks 
- It is hard to believe that programmers keep making the same mistakes over and over again. Buffer overflows have been in the news for years now, every security page has warnings to coders, and almost every new programming book has a section on how NOT to make this kind of mistake. Yet it keeps happening.
Badram, Badmem, and Memtest86.bin  by Drag Sidious
- When you get almost-random stuff going wrong like that, and you know that your using what should be a fairly stable OS the likely culprit is going to be flaky hardware
Google Maps Beta  by Dirk Hart
- This app is surprisingly fast and has obvious features other map servers lack. The first thing I did was type in Boston, MA which is pretty close to home.
Using Rsnapshot 
- Rsnapshot is a Perl script that uses rsync to create incremental backups. You can download it from http://www.rsnapshot.org/. The first thing to decide is where you will keep your backups. By default, the configuration file points them at /.snapshots. Although the script is smart enough to avoid containing its own directory in backups (because it would lead to recursion), I'd still rather have this directory somewhere off the backup set if possible. In my case, I use this for backup of a remote webserver, so /.snapshots is fine. This, and everything else, is set in the configuration file (/etc/rsnapshot.conf by default). All elements have to be tab separated.
MySQL Cluster setup and HowTo  by LOD.com
- MySQL Cluster Server is a fault-tolerant, redundant, scalable database architecture built on the open-source MySQL application, and capable of delivering 99.999% reliability.
SSH passphrases and keys 
- As we left it, we have a specific user or users allowed ssh access. You have to know that user name and password to login, but you can do so from anywhere in the world with no prior arrangements. That's convenient: it lets you use any ssh client on any machine. For example, I can be at a client and ssh back to my home machine. If we assume that I'm not worried about a fake ssh client that is going to steal my passwords (though that's certainly possible), and I have the "lock after bad attempts" set up, this is fairly safe.
Map network drive, connect as different user to same Server 
- How to map an XP network drive more than once even though XP doesn't want you to do that.