[2003-03-27] Why not differential backups?
I get this question frequently. It's usually triggered either because the tape device can't hold an entire backup set or because the time required for backup interferes with productive work. Most of the time this can be easily remedied by a larger or faster storage device, but someone is bound to bring up the idea of differential backups. The idea is that you create a full backup that has everything, and from then on, you only backup the files that have changed. Presumably that's a smaller set of files and therefore this solves the space or time problems. Usually the full backup is refreshed on some schedule and the process starts again. There are variants on the theme; for example the differential may include all files that have changed since the last full backup rather than just those that have changed since the last differential. That sort of scheme eventually ends up with the differential containing any and all files that ever change, no matter how infrequently; the full backup is the source of everything else.

[2003-03-27] Multitech RF550VPN SOHO VPN Router
Multitech's new SOHO RF550VPN Router is an inexpensive ($179.00 list ) Internet access router with VPN capabilities suitable for home or small office use. Features not found in lower end products include
  • Five (5) IPSEC VPN tunnels
  • Automatic dialup to emergency ISP if WAN connection fails
  • Both client and WAN side filtering
  • Virtual servers (inward port redirection)
  • Redirect RF550VPN logging to a syslog server
  • Flash upgradable firmware

[2003-03-27] RS232 Wiring Diagrams
Meanings of pins in DB25 order:

[2003-03-26] Documenting Your Network
Undocumented networks are extremely common. Many times this is related more to the difficulty of keeping the documentation up to date rather than to the difficulty of the documentation process itself. Many LAN Administrators had big dreams at one time of keeping elaborate drawings detailing every last aspect of the network. However, networks tend to change too frequently for such drawings to stay current. In spite of the difficulty, having a well documented network can help you solve problems quickly when they arise and is vital to the overall security of your network. In this article, we’ll discuss some alternative documentation methods that are more practical in the ever changing world of networks.

[2003-03-25] Why Production servers shouldn't have external interfaces
Read the Disclaimer People sometimes want to use their application servers as firewalls. This seems attractive at first glance: slap in another network card, add some packet filtering, tighten the system down a bit and connect it to the outside world. Cheap and quick, but a very bad idea.

[2003-03-25] Understanding IPTABLES
Disclaimer Packet filtering is something I've always hard a hard time getting my head around. Not the basics; that's easy enough. It's just the incredible level of detail, the difficulty of keeping it all in your head at once. And then, of course, there are all the different flavors: ipfw, ipfilters, ipchains, and now iptables. It gets more than a little confusing, and I've never taken the time for more than a cursory look at any of them.

[2003-03-20] The Network Router as Unsung Hero
Greater intelligence in routers could enable them to look inside a data packet and, for example, determine the content of a packet, according to IDC research manager Paul Strauss.

[2003-03-20] Cisco To Bolster Linksys Product Line
Cisco Systems plans to beef up newly acquired Linksys products to improve the overall price/performance and functionality of those offerings, said Charlie Giancarlo, senior vice president and general manager of product development at Cisco.

[2003-03-19] Who Cares About the Fastest Internet Ever?
The latest land-speed record in Internet transmission was all about networking smarter, not faster. But that's not how it was publicized.

[2003-03-03] A Linux Fax Server for a Windows Network
Introduction The firm I work for had a fax system integrated in the corporate e-mail platform, Microsoft Exchange, for sending and receiving. One day after a software upgrade, the system broke. We needed to find something with the equivalent functionality but with the following conditions:

[2003-03-03] Backing Up and Restoring Windows 2000
Intro Backing up your data can be one of the most important things that you do in your IT and/or home life. You never seem to miss something until it is gone. If you want to spend more time making money and not redoing things that you have already done then make sure you back it up.


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