#ebook #pdf #mobi #python #cookbook

nethogs is used to monitor network traffic. You can see which processes use the most bandwidth and hogs the network.

Installtion on debian:

apt-get install nethogs

You can give the nethogs a network interface to see what's going on under the hood:

nethogs eth0

The output would something like:

PID USER       PROGRAM                                                       DEV        SENT      RECEIVED
9023 root      python                                                        eth0        6.083     175.811 KB/sec
20745 root     python                                                        eth0        2.449      45.715 KB/sec
11934 www-da.. nginx: worker process                                         eth0      131.580      20.238 KB/sec
25925 root     /usr/bin/python                                               eth0        3.674      10.090 KB/sec

When nethogs is open, you can press r in order to sort based on RECEIVED or press s to sort based on SENT packets. To change the mode that it is shown for KB/sec press m multiple times and see the output.

#network #sysadmin #linux #nethogs #nethog #network #eth0

#ebook #pdf #mobi #docker #jenkins

How to turn a dictionary into a string?

extra_data = {'iso': 'IR', 'address': 'Iran - Tehran - Azadi'}
 ' - '.join('{}:{}'.format(key, val) for key, val in extra_data.items())

The output would be:

iso:IR - address:Iran - Tehran - Azadi

NOTE: it could come in handy in case you want to store a variable dictionary structure into NO-SQL database.

#python #dictionary #string

#css #chestsheet

The PDF Version

#html #cheatsheet

https://askubuntu.com/questions/726601/nethogs-%E2%86%92-creating-socket-failed-while-establishing-local-ip-are-you-root

#nethogs #debian #linux #bug

How do you upgrade Icinga2 from a very old version?

The short answer is that you need to do an incremental upgrade on its database.

But how exactly?

apt-get update

apt-cache policy icinga2-ido-mysql

The candidate section displays what version is available for you system. Do the same for icingaweb2:

apt-cache policy icingaweb2

Upgrade these packages alltogether:

apt-get upgrade -o Dpkg::Options::="--force-confold" -y

Update icinga2 packages:

apt-get upgrade icinga2 icinga2-bin icinga2-common icinga2-ido-mysql libicinga2
 apt-get install icinga2-bin
 apt-get install icinga2

Now check icinga2 log in tail -f /var/log/icinga2/icinga2.log, you may see errors like:

[2017-12-21 12:00:22 -0600] critical/IdoPgsqlConnection: Schema version '1.14.2' does not match the required version '1.14.3' (or newer)! Please check the upgrade documentation at https://docs.icinga.com/icinga2

Here you need to upgrade MySQL schemas, go to /usr/share/icinga2-ido-mysql/schema/upgrade path and now import new schemas to Icinga2 MySQL database. As I was in version 2.6.0 I went for 2.8.0:

mysql -u icinga2 -p icinga2 < 2.8.0.sql

It will prompt for password of user icinga2, enter the password and go on.

The content of MySQL Schemas is as follows:

2.0.2.sql  2.1.0.sql  2.2.0.sql  2.3.0.sql  2.4.0.sql  2.5.0.sql  2.6.0.sql  2.8.0.sql  2.8.1.sql

NOTE: to get the password for user icinga2 open /etc/icinga2/features-enabled/ido-mysql.conf file and get the password from here.


#linux #icinga2 #monitoring #icinga2 #icingaweb #upgrade

How to get list of network interfaces using nagios?

In nagios plugins there is a script called check_nwc_health that can be used to report network interfaces of a remote server. In order to check interface usage of remote server network cards:

cd /usr/lib/nagios/plugins
 ./check_nwc_health --mode interface-usage -H 172.17.131.12 -C YOUR_COMMUNITY_STRING

Give your host address in -H section and your community string in -C param.

#nagios #network #network_usage

The best explanation about load average:

http://blog.scoutapp.com/articles/2009/07/31/understanding-load-averages

#linux #load #load_average #cpu

In case your upgrade failed, try to start icinga service and in the meantime check the logs in another console:

service icinga2 start

Check logs to see what is the error:

tail -f /var/log/icinga2/icinga2.log

If it point to a specific config file, change the config as reported or in case you don't need it remove it. It happened for me on another Icinga2 server and I removed the old config and tried to apply the new schemas. It gave another error on mysql grants, I gave all permissions to the icinga2 user:

mysql -u root -p
 GRANT ALL PRIVILEGES ON icinga2_database_name.* TO 'icinga2_username'@'localhost'
 flush privileges;

Now all things should be up and working now.

#icinga2 #monitoring #upgrade #schema_update #icinga

Generate random valid users agent for your bot crawlers in Python:

https://pypi.org/project/user_agent/

#python #user_agent #crawl #web_scraper

How to Load & Parse YAML file in Python?

To install YAML library:

pip install pyyaml

To load a YAML file:

>>> import yaml
 >>> print yaml.load("""
 ... name: Vorlin Laruknuzum
 ... sex: Male
 ... class: Priest
 ... title: Acolyte
 ... hp: [32, 71]
 ... sp: [1, 13]
 ... gold: 423
 ... inventory:
 ... - a Holy Book of Prayers (Words of Wisdom)
 ... - an Azure Potion of Cure Light Wounds
 ... - a Silver Wand of Wonder
 ... """)

To convert a dictionary to a YAML file:

>>> print yaml.dump({'name': "The Cloak 'Colluin'", 'depth': 5, 'rarity': 45, 'weight': 10, 'cost': 50000, 'flags': ['INT', 'WIS',     'SPEED', 'STEALTH']})

#python #yaml #pyyaml #load #dump

How to localize a UTC date?

import pytz
 import datetime

 date_format = '%Y-%m-%d %H:%M:%S'
 dt = datetime.datetime.strptime('2018-12-12 00:00:00', date_format)
 utc_tz = pytz.timezone('UTC')
 utc_d = utc_tz.localize(dt)
 teh_tz = pytz.timezone('Asia/Tehran')
 dt = utc_d.astimezone(teh_tz)

#localize #timezone #pytz #astimezone #replace

#ebook #download #sql #postgreql #pdf

#pdf #ebook #postgresql

https://developer.mozilla.org/en-US/docs/Learn/Server-side/Django

#django #tutorial #mozilla