Network Manager post-up script (dispatcher script)

Network manager is supposed to be much better than network, how so?

it supports dnsmasq for one…

Dnsmasq with netowrkmanager

Local name resolution

Also Network Manager supports dispatcher scripts. How can that help? For one, I used to send interface up emails. To do so, all I had to do was put the following script in “/etc/NetworkManager/dispatcher.d”

#!/bin/sh

cd /etc/sysconfig/network-scripts
. ./network-functions

[ -f ../network ] && . ../network

# Notify programs that have requested notification
IF=$1
STATUS=$2

cat

dnsmasq local name resolution with NetworkManager

Network Manager suports starting dnsmasq which helps you have a local cache for DNS thus getting faster resolution for the DNS queries.

Dnsmasq with netowrkmanager

So, one thing that I have been thinking about is having a local name resolution for the VMs. So, I wanted something like this to work:

vm1 => 172.17.42,1

vm2 => 172.17.42,2

and so on …

To achieve this and reverse dns to work, we will add the entries in file “/etc/NetworkManager/dnsmasq.d/hostnames“. Just one more problem, adding so many entries manually? So, to help you with that, I created this small script:

ShellCheck – check basic POSIX shell script errors

Here is description of the tool:

Description : The goals of ShellCheck are:

• To point out and clarify typical beginner’s syntax issues,
  :   that causes a shell to give cryptic error messages.

• To point out and clarify typical intermediate level semantic
  :   problems, that causes a shell to behave strangely and
  :   counter-intuitively.

• To point out subtle caveats, corner cases and pitfalls, that may
  :   cause an advanced user’s otherwise working script to fail under
  :   future circumstances.

To install

evvsubst – substitute variables in text in shell

First you need to install gettext, which by the way might be already installed, however you can install with

dnf install gettext

Details of the package:

Name        : gettext

Arch        : x86_64

Epoch       : 0

Version     : 0.19.4

Release     : 4.fc22

Size        : 4.6 M

Repo        : @System

Summary     : GNU libraries and utilities for producing multi-lingual messages

URL         : http://www.gnu.org/software/gettext/

License     : GPLv3+ and LGPLv2+

Description : The GNU gettext package provides a set of tools and documentation for

producing multi-lingual messages in programs. Tools include a set of

conventions about how programs should be written to support message

catalogs, a directory and file naming organization for the message

catalogs, a runtime library which supports the retrieval of translated

messages, and stand-alone programs for handling the translatable and

the already translated strings. Gettext provides an easy to use

library and tools for creating, using, and modifying natural language

catalogs and is a powerful and simple method for internationalizing

programs.

Usage examples:

Easily monitor and archive your system log reports.

If you want to monitor your server logs and also like them to be emailed then just Logwatch may not be sufficient. It sends you a mail but does not archive them, so head over to epylog

Name        : epylog

Arch        : noarch

Epoch       : 0

Version     : 1.0.7

Release     : 9.fc22

Size        : 151 k

Repo        : fedora

Summary     : New logs analyzer and parser

URL         : https://fedorahosted.org/epylog/

License     : GPLv2+

Description : Epylog is a new log notifier and parser which runs periodically out of

cron, looks at your logs, processes the entries in order to present

them in a more comprehensive format, and then provides you with the

output. It is written specifically with large network clusters in mind

where a lot of machines (around 50 and upwards) log to the same

loghost using syslog or syslog-ng.

To install :

tlp – optimize and maximize your battery power.

So, you are having issues with battery life on linux. Then head over to tlp project.

TLP brings you the benefits of advanced power management for Linux
without the need to understand every technical detail. TLP comes
with a default configuration already optimized for battery life.
Also an optional install of the smartmontools package enables hard
disk SMART data in tlp-stat (smartctl).

Install with following command

dnf install tlp
#or
yum install tlp

retext – Editor for restructured text

restructured text is a simple text editor for markdown/restructured text which can show preview as well. So, here is some details on same :

Name        : retext
Arch        : noarch
Epoch       : 0
Version     : 5.0.1
Release     : 7.fc22
Size        : 412 k
Repo        : @System
Summary     : Text editor for Markdown and reStructuredText
URL         : http://sourceforge.net/p/retext/home/ReText
License     : GPLv3+
Description : ReText is a simple but powerful text editor for Markdown and reStructuredText.

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