Sep 302014
 

tux-terminal.jpg
Article by Daniel Miessler first posted on his blog

lsof is the sysadmin/security über-tool. I use it most for getting network connection related information from a system, but that’s just the beginning for this powerful and too-little-known application. The tool is aptly called lsof because it “lists openfiles“. And remember, in UNIX just about everything (including a network socket) is a file.

Interestingly, lsof is also the Linux/Unix command with the most switches. It has so many it has to use both minuses andpluses.

usage: [-?abhlnNoOPRstUvV] [+|-c c] [+|-d s] [+D D] [+|-f[cgG]]
 [-F [f]] [-g [s]] [-i [i]] [+|-L [l]] [+|-M] [-o [o]]
 [-p s] [+|-r [t]] [-S [t]] [-T [t]] [-u s] [+|-w] [-x [fl]] [--] [names]

As you can see, lsof has a truly staggering number of options. You can use it to get information about devices on your system, what a given user is touching at any given point, or even what files or network connectivity a process is using.

For me, lsof replaces both netstat and ps entirely. It has everything I get from those tools and much, much more. So let’s look at some of its primary capabilities:

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Sep 132014
 

Systemd
Article by Stuart Burns first posted on Openlogic.com

With Red Hat Enterprise Linux 7 released and CentOS version 7 newly unveiled, now is a good time to cover systemd, the replacement for legacy System V (SysV) startup scripts and runlevels. Red Hat-based distributions are migrating to systemd because it provides more efficient ways of managing services and quicker startup times. With systemd there are fewer files to edit, and all the services are compartmentalized and stand separate from each other. This means that should you screw up one config file, it won’t automatically take out other services.

Systemd has been the default system and services manager in Red Hat Fedora since the release of Fedora 15, so it is extensively field-tested. It provides more consistency and troubleshooting ability than SysV – for instance, it will report if a service has failed, is suspended, or is in error. Perhaps the biggest reason for the move to systemd is that it allows multiple services to start up at the same time, in parallel, making machine boot times quicker than they would be with legacy runlevels.

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Sep 082014
 

Guest post by Sophie Davidson

Modern day criminals are no longer entering banks with ski masks and pistols. Today’s felons are moving into cyberspace to accomplish their nefarious goals.

Remember the old adage, “a criminal always returns to the scene of the crime”? It turns out this maxim holds a lot of weight with regards to DDoS cybercrime.

Double DDoS

Recent research from BT revealed that about 41% of online businesses surveyed were victims of DDoS in the last 12 months. The more notable findings of the research showed that, of those attacked, over 78 percent were subsequently hit a second time shortly thereafter.

Distributed Denial of Service attacks or DDoS encompass a large variety of cyber threats designed to overwhelm a target’s server, or jam up their network. By disrupting a target’s resources, the hackers succeed in preventing normal traffic (such as users or customers) from passing through.

The effects of these attacks are potentially devastating. After being hit by a strong attack, it takes on average at least 12 hours to offer full service back to users.

What can happen in 12 hours? This sort of disruption could mean losing hundreds of thousands of dollars in revenue. Or, perhaps worse, the trust between the user and the online business, built up over months or years, could be lost in a matter of minutes.
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Aug 312014
 

Some time ago I posted an article about shelr.tv a website and a service that was made to allow you to share your terminal records directly from the website.

Now the website of shelr.tv seems dead and so I’ve took a look around to see if there are similar websites and I’ve found commands.com.

For what I can see from their homepage it’s a service similar to the other, so let’s test it.
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Aug 282014
 

Article by Himanshu Arora first posted on http://mylinuxbook.com/

Sometimes a computer system is connected to so many file-systems (in parallel) that managing these connections becomes a complex task. If a user’s work involves interacting with local, external and remote file-systems then he/she would definitely feel a need for a connection management software to manage all the connections centrally.

Looking for a simple connection manager? Try out Gigolo.

gigolo-main

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