Python for Network Engineers

This repo contains Scripts which are explained in the YouTube Channel NetworkEvolution

List of Directories in this Repository:

• 00_Python_Scripts_from_Youtube_Playlist
• 01_Paramiko_Sample_Scripts
• 02_Configure_Device_Using_CSV
• 03_Cisco_Config_Parser_Regex

Summary of each Directory

---

Directory : 00_Python_Scripts_from_Youtube_Playlist

This directory contains all the Scripts explained in the below YouTube playlist which has more than 70 Videos.

Training starts from a very beginner level like: How to initiate SSH Connection to the Device using Paramiko To Intermediate level of Using NETCONF/YANG, RESTCONF etc

List of all the Scripts

Click here for Complete Videos Playlist In YouTube :Python Learning for Network Engineers

For the Complete Scripts and Video maps please access the folder "`00_Python_Scripts_from_Youtube_Playlist`" in this Repository

These Python scripts Contains Tutorials on:

• Paramiko
• Netmiko
• Nornir
• NAPALM
• Ansible
• NETCONF/YANG
• RESTCONF
• Regex For Parsing
• CSV for Bulk Configuration
• How to use text file for Configuration

---

Directory : 01_Paramiko_Sample_Scripts

This directory contains Scripts which explains how to use Paramiko Library for communicating with Cisco Devices.

• Demonstrates the use of SSH Hostkey policy. Different ways to use hostkey policies :

session.set_missing_host_key_policy(paramiko.AutoAddPolicy())
session.load_host_keys('/home/evolve/.ssh/known_hosts')
session.set_missing_host_key_policy(paramiko.WarningPolicy())

• SSH Keybased Authentication Using Paramiko:
• Paramiko SSH exec_command Example
• Paramiko invoke_shell example
• SSH Password Based Authentication

List of Scripts in the Directory

01_ssh_host_key_policy.py
02.1_ssh_key_cisco_exec_command.py
02.2_ssh_key_cisco_invoke_shell.py
02.3_ssh_key_cisco_invoke_shell_fn.py

Click here for Complete Paramiko Scripts Tutorial Playlist In YouTube :01_Paramiko_Sample_Scripts

For the Complete Scripts and Video maps please access the folder "`01_Paramiko_Sample_Scripts`" in this Repository

---

Directory : 02_Configure_Device_Using_CSV

This directory contains Scripts which explains how to read Device IP Address and configuration lines from CSV file and configure respective devices using Python.

• Sample CSV FIle Used for Configuring the Device :

• The above CSV file will create a Dictionary in below format

conf_dict={'192.168.0.50': ['terminal len 0',
                  'config t',
                  'int gi1',
                  'no shut',
                  'exit',
                  'exit',
                  'show ip int brie',
                  'show run int gi1'],
 '192.168.0.51': ['terminal len 0',
                  'config t',
                  'int lo0',
                  'ip add 10.0.0.1 255.255.255.0',
                  'int lo1',
                  'ip add 11.0.0.1 255.255.255.0',
                  'do show run int loopback0',
                  'do show run int loopback1'],
 '192.168.0.53': ['terminal len 0', 'config t', 'int gi3', 'no shut'],
 'csr1.test.lab': ['terminal len 0',
                   'config t',
                   'int gi2',
                   'no shut',
                   'ip address 2.2.2.2 255.255.255.0',
                   'exit',
                   'exit',
                   'show ip int brie',
                   'show run int gi2']}

List of Scripts in the Directory

• 01_config_in_row.csv : How to read Content from CSV file in row format : Script Demonstration Videos
• 01_csv_reader_row.py : How to read Content from CSV file Using Reader format : Script Demonstration Videos
• 02_config_in_column.csv : How to read Content from CSV file in Column format :Script Demonstration Videos
• 02_csv_reader_column.py : How to read Content from CSV file in Column format using Reader : Script Demonstration Videos
• 03_csv_DictReader_column.py : How to read Content from CSV file in Column format using DictReader :Script Demonstration Videos

Click here for Complete CSV Videos Playlist In YouTube :02_Configure_Device_Using_CSV

For the Complete Scripts and Video maps please access the folder "`02_Configure_Device_Using_CSV`" in this Repository

---

Directory : 03_Cisco_Config_Parser_Regex

This directory contains Scripts which explains how to parse configuration lines from Cisco Devices Using Regex in Python

Sample Parsed Output :

*Show Version Parser

*Show Running Config Parser Output:

• Regex Patterns Used for Show Version Parser:

version_pattern = re.compile(r'Cisco .+ Software, Version (\S+)')
model_pattern = re.compile(r'cisco (\S+).+bytes of memory\.')
serial_no_pattern = re.compile(r'Processor board ID (\S+)')
uptime_pattern = re.compile(r'(.+) uptime is (.*)')

• Regex Patterns Used for Show running Parser:

hostname_pattern = re.compile(r'hostname (\S+)')
domainname_pattern = re.compile(r'ip domain name (.+)')
pid_pattern = re.compile(r'license udi pid (\w+) sn (\S+)')
netconf_pattern = re.compile(r"netconf-yang\r\n")
username_pattern = re.compile(r'username (\S+) privilege (\d{2})')
interface_pattern = re.compile(r'interface (\S+[.]?\d*)\r\n.+?\r?\n?\s?ip address ([\d\.]+) ([\d\.]+)')
interface_prop_pattern = re.compile(r'interface (?P<name>\S+[.]?\d*)\r\n\s?.+?\r?\n?\s?ip address (?P<ip_aadress>[\d\.]+) (?P<mask>[\d\.]+)')
default_route_pattern = re.compile(r'ip route 0.0.0.0 0.0.0.0.+?([\d.]+)\r\n')
static_route_pattern = re.compile(r'ip route (?P<dst_subnet>[^0][\d\.]+) (?P<mask>[^0][\d\.]+) (?P<next_hop>[\d\.]+)')

List of Scripts in the Directory

• 01_parse_Show_ver_SSH.py : Parse Show Version Output over SSH : Script Demonstration Videos
• 01_parse_show_ver_from_file.py : Parse Show Version Output from Text file : Script Demonstration Videos
• 02_parse_show_run_from_file.py : Parse Show Run Output from Text file :Script Demonstration Videos
• 02_parse_show_run_from_SSH.py : HParse Show Run Output from SSH : Script Demonstration Videos
• command_output_to_txt.py : Save Multiple Show Commands to text file :Script Demonstration Videos

Click here for Complete Cisco Configuration Parsing Videos Playlist In YouTube

For the Complete Scripts and Video maps please access the folder "03_Cisco_Config_Parser_Regex" in this Repository