redhat

How to do MAC address packet filtering using IPTables

Media Access Control address (MAC address) or Ethernet Hardware Address (EHA) or hardware address or adapter address is a quasi-unique identifier attached to most network adapters (NICs). It is a number that acts like a name for a particular network adapter, so, for example, the network cards (or built-in network adapters) in two different computers(…)

How to Determine RedHat and Fedora release version

A quick blog post on how to determine your Fedora release name and its release version. For several years of staying and working under a company with multiple linux distributions and versions, multiple OS upgrades and server redundcancy backups makes it somehow confusing and difficult to differentiate which release name and version was a specific(…)

How to Install Bandwidth Shaper – Trickle on Fedora

Shaping bandwidth traffic has been a usual part of job function from any IT company infrastructure providing online services to the web. From small scale company to enterprise scale, bandwidth shaping needs to be implemented and applied properly and effectively. Here’s one lightweight linux traffic shaper that makes use of existing network traffic shaping that(…)

How to Display Lines That Starts With A Given String

Matching strings can be counted using grep, cat, sed. Matching strings can be sorted and even omitted for matching repetitions using sort and uniq. They can also be highlighted during the string parsing operation via grep. More can be done using awk. But have you ever tried to display the first occurrence of matching line(…)

How to Extremely Powerful Linux Password Sniffer

Password Sniffer on Linux? Yep, we all need to be informed of passwords being sniffed out! I would not entail those details and cover specific issues of identifying your network securities as that would be large enough to be covered here and case to case basis. However, those two words are being mentioned here and(…)

How to Copy and Paste A Text File into Another Text File via Terminal

Let us view two example of text files namelyh textfile1.txt and textfile2.txt # cat textfile1.txt RedHat Fedora CentOS # cat textfile2.txt Enterprise Version Core Version 9 Linux Distro Now, let us merge or combine two text files using the linux paste command # paste textfile1.txt textfile2.txt result: RedHat Enterprise Version Fedora Core Version 9 CentOS(…)

How to Join Two Text Files with Common Columnar Field via Terminal

HowTo: Join Two Text Files with Common Columnar Field via Terminal Say we have two text files, namely test1.txt and test2.txt, with data content as follows # cat test1.txt first Fedora second Redhat third CentOS # cat test2.txt first Core 9 second Enterprise Version third Free OS Now, the simplest approach to merge data contents(…)

How To Create Separate SSH Log File for Specific SSH Clients

By default, OpenSSH dumps log messages to /var/log/secure authentication log file. The need to log particular host or group of IP address to separate SSH log file is needed at times to further log SSH details for further record and monitoring. Create Separate SSH Log File for Particular SSH Client Log Attempts Here’s how to(…)

How To Send System Message To FTP Clients via TCP Wrapper

From recent posts, granting access (allow and deny) restrictions to particular services is a good additional security practice anybody could use of nowadays. There are some system admins that prefer sending system message or account status when denying access to particular clients or hosts. Sending service message or service system status to particular hosts or(…)

How To Enable IP Forwarding in Linux

By installation default, Linux distribution such as Redhat, CentOS, White OS, and Fedora comes with IP Forwarding disabled. The reason for this is that default linux installation, whether desktop or server, does not consider a default OS installation of forwarding IP packets and request by default, as the linux OS is not fully aware of(…)

How To Bypass DNS Log Monitoring By Your ISP

Resolving domains into human-readable IP addresses requires DNS IP addresses from your ISP. The DNS nature of resolving domain names into its equivalent IP addresses provides a lot of things to you and your ISP provider. DNS Nature One major thing that this DNS nature setup provides you is browsing convenience. Since DNS resolves domains(…)

Top 100 of the Best (Useful) OpenSource Applications

The following is a list of about 100 of the best OpenSource Applications, that actually help make Linux more usable for people. It is my hope that this list shows potential Linux users that there really is a large, effective, productive and usable range of free, OpenSource applications. For existing Linux users (like myself), I(…)