Taming the Wild Netfilter
Using Netfilter's stateful rules, you can actually increase the security of your home system with less effort by making judicious use of its connection tracking. Many more options are also available to you. This article scratches only the surface. I recommend you make use of Rusty's Unreliable Guides available on the Netfilter site (mentioned earlier).
For home users with simple needs, keep your firewall simple. I do not recommend most firewall tools and scripts because they layer unnecessary complexity into your firewall. If you don't understand a rule, don't implement it. The first three stateful rules (using the -m state rule) will keep you in good stead. If an attacker has already been in and compromised a system, the rules won't help. They also won't protect you against e-mail-based trojans, but they will protect against direct attacks. I suggest, if you don't use IRC, you log and drop outgoing IRC connections:
$IPT -j filter -I tcprules -p tcp --destination-port 6667 -j LOG --log-prefix "IRC attempt " $IPT -j filter -I tcprules 2 -p tcp --destination-port 6667 -j DROP
Also, if you don't need anyone entering your network, don't open any ports (as we did in our second example). This article did not discuss how to segregate your network properly to isolate internet-accessible systems from trusted internal systems. If you require this level of complexity, and your risk assessment asks for it, it might be time to call for knowledgeable help.
Practical Task Scheduling Deployment
One of the best things about the UNIX environment (aside from being stable and efficient) is the vast array of software tools available to help you do your job. Traditionally, a UNIX tool does only one thing, but does that one thing very well. For example, grep is very easy to use and can search vast amounts of data quickly. The find tool can find a particular file or files based on all kinds of criteria. It's pretty easy to string these tools together to build even more powerful tools, such as a tool that finds all of the .log files in the /home directory and searches each one for a particular entry. This erector-set mentality allows UNIX system administrators to seem to always have the right tool for the job.
Cron traditionally has been considered another such a tool for job scheduling, but is it enough? This webinar considers that very question. The first part builds on a previous Geek Guide, Beyond Cron, and briefly describes how to know when it might be time to consider upgrading your job scheduling infrastructure. The second part presents an actual planning and implementation framework.
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|Stunnel Security for Oracle||Jul 28, 2016|
|SUSE LLC's SUSE Manager||Jul 21, 2016|
|My +1 Sword of Productivity||Jul 20, 2016|
|Non-Linux FOSS: Caffeine!||Jul 19, 2016|
|Murat Yener and Onur Dundar's Expert Android Studio (Wrox)||Jul 18, 2016|
- Stunnel Security for Oracle
- The Firebird Project's Firebird Relational Database
- Murat Yener and Onur Dundar's Expert Android Studio (Wrox)
- SUSE LLC's SUSE Manager
- Managing Linux Using Puppet
- My +1 Sword of Productivity
- Non-Linux FOSS: Caffeine!
- Doing for User Space What We Did for Kernel Space
- Google's SwiftShader Released
- SuperTuxKart 0.9.2 Released