Graylog2 install Slack Notifications

The graylog Marketplace has a great document on getting started, but I ran into one snag adding HTTPS certificate to java store for hooks.slack.com. For reference here is link to marketplace  Required Graylog version: 2.0 and later. Detailed alarm notification and message output: This plugin can notify Slack or Mattermost channels about triggered alerts in Graylog (Alarm Callback) and also forward […]

Remove Whitespace from File and Directory Name

How to remove all white space from directory names and file names recursively. Use rename (aka prename) which is a Perl script which may be on your system already. Do it in two steps: find -name “* *” -type d | rename ‘s/ /_/g’ # do the directories first find -name “* *” -type f | rename ‘s/ […]

Sensu Uchiwa Dashboard “Internal 500 error”

Recently had an issue with ruby resolving to IPV6 resulting in failed login attempts for Uchiwa dashboard with Sensu-API. Uchiwa was reporting “Internal 500 error” and Sensu Log Message showed the following {“timestamp”:”2017-06-21T19:17:36.362831-0400″,”level”:”warn”,”message”:”transport connection error”,”reason”:”possible authentication failure. wrong credentials?”,”user”:”sensu”}   This magical line helped troubleshoot the issue. IPV6 Example ## /opt/sensu/embedded/bin/ruby -rresolv -e ‘puts Resolv.getaddress […]

Block updates of a specific package

If you wanting to block updates of a specific package you can use the command “apt-mark” to put a hold on the package. There are various techniques to disable/lock package from install, upgrade and remove in Debian Linux and its derivatives such as Ubuntu and Linux Mint. The command apt-mark will mark or unmark a […]

Increase ELK ElasticSearch Performance

Tip #1: Know Your Deployment Topology Before You Set Configs Loggly is running ES 0.90.13 with separate master and data nodes. We won’t be going into too much detail about that right now (look out for a subsequent post), other than to say that you need to determine your deployment topology in order to make […]

Finding UUID to Identify Partitions

Linux’s ext2/ext3 filesystem uses UUID UUID benefits As a sesonded UNIX admin I have to deal with various data storage technologies such as SAN, iSCSI, DAS, scsi disks volumes. Sometime you may need to move storage from one device to another and updating /etc/fstab can be pain in a$$. With UUID Linux kernel should automatically […]

apt-get-repository Command is Missing

Problem: apt-get-repository Command is Missing I was trying to install the latest version of git from the Ubuntu Git Maintainers Team and I needed to add a Personal Package Archive (PPA) to the Software Sources. But when I tried to do this, I got an error: sudo: add-apt-repository: command not found Solution: Install the software-properties-common […]

Find Largest files on Linux System

How do I find the largest top files and directories on a Linux or Unix like operating systems? Sometime it is necessary to find out what file(s) or directories are eating up all your disk space. Further, it may be necessary to find out it at the particular location such as /tmp or /var or […]

Lets look at CronTab

About crontab The crontab is a list of commands that you want to run on a regular schedule, and also the name of the command used to manage that list. crontab stands for “cron table,” because it uses the job scheduler cron to execute tasks;cron itself is named after “chronos,” the Greek word for time.

Easy Install PHP Mcrypt Extension on Ubuntu Linux

Most of web-based application development todays were developed using database. The most popular one is using PHP and MySQL. When developing using MySQL most of beginners were using phpMyAdmin as their power tools in database CRUD (Create-Read-Update-Delete) as well as databases/tables creation and manipulation. PhpMyAdmin supports encryption feature which enables database developers to raise their […]

Tailing Log files in Colour

grc will execute command command with optional parameters [args] piping its stdout or stderr into grcat, with apropriate configuration file. Configuration file for grc is determined by /etc/grc.conf file. Format of /etc/grc.conf: each entry consists of 2 lines, between entries there can be any number of empty lines or lines beginning with # (comments)

Oracle Yum Repo – Setup

Developed and tested to support demanding workloads, such as Oracle Database. Allows features such as Btrfs, DTrace, OCFS2, and Linux Containers to be used across multiple major releases (Oracle Linux 6.4 and later). Able to parallelize network and disk IO and Efficiently runs on systems with many cores and threads and NUMA nodes. Optimized for solid state drives. Supports data […]

ISO Image Creation

Previously I used the CAT command and recently came across READOM command that supports error correction from a cdrom device. #cat /dev/cdrom > /home/username/test.iso can be replaced with the right tool for the job #readom dev=/dev/cdrom f=/home/username/test.iso You can also write that image using the #wodim -v -eject /home/username/test.iso