Posts Categorized: linux

Top of the Tops 2013

A revised list of my favourite ‘tops’ htop htop can provide a little more info than the traditional ‘top’ – I like how it shows the amount of memory usage minus the cache. iftop To check network connectivity use iftop: iptraf Like iftop but with more options and even the ability to show traffic by… Read more »

Some Linux LPI 102 Exam Questions

I just passed my Linux LPI 102 exam today and thought I would try to remember a few of the 60 questions in case I ever have to take a refresher – here is about half of them. I can’t remember the wording exactly for these questions so take with a pinch of salt: 1…. Read more »

Command Line Wireless Trouble-shooting

I wanted to compare the command line output of a working Wifi connection versus a connection at a location that was giving us trouble. To do so I used Ubuntu (12.10) on a laptop and used the following commands – in a script if necessary. First a configuration file to use with the wpa-supplicant –… Read more »

Fail2Ban Custom Action

I decided to experiment with creating a central database to hold the IP addresses banned by various servers / honeypots running Fail2Ban – so that the information could be used as a source for IPtables or TCPWrappers to protect other servers. I created the file /etc/fail2ban/action.d/qshield.conf and in it placed the following:

Then editied… Read more »

Dynamic DNS to Raspberry Pi

I now have my Raspberry Pi hanging off my router – just two cables – a USB cable to the USB port on the router for power and one ethernet cable. 1. Static IP Address I edited the file: /etc/network/interfaces replacing:

with

So that my Pi would be available at a static address. I… Read more »

FFmpeg Convert FLV to AVI

I was having difficulty converting an FLV file saved from iPlayer. The command to successfully convert the file was:

Samsung TV Channel Editing

samtoolbox

I wanted to configure the channel numbers on my Samsung LE40C580 but using the remote control on the TV was a bit frustrating. I found that within the TV menu I could export/import the channel list to a USB drive. Changing the file extension to .zip allows extracting the file to view the contents: I discovered… Read more »

Bash Shell Script to Automate FTP File Transfer

A little script to send a backup file to a remote FTP server:

Then run it every day from Cron.

IPTables Custom Chain for SSH access

I wanted a custom IPTables firewall chain to allow SSH access to a machine. The idea is that users hit a web page that adds their dynamic IP address to a list and then a script inserts that IP address into IPTables to allow SSH access. I achieved this as follows. In /etc/sysconfig/iptables I added:

Read more »

Adaptec Hardware RAID controller on Sun 4150

On our Oracle Sun x4150’s the Hardware Raid can be checked after installing the StorMan software which is available (as StorMan-6.40.x86_64.rpm)  in the software bundle for x4150s available after logging in to the Oralce support website and locating the downloads for x4150s. The download is pretty big (931MB) when the 39MB RPM is all you are… Read more »