firewallfc

[firewallfc]

Advantages and disadvantages of Bus topology

Advantages -It works well for a small network. -Easy to implement -It requires a smaller number of cables as compared to a star topology. -It is easy to connect or remove devices without affecting the network. -Very cost-effective

Disadvantages -This is not great for a large network. -Complete network will fail if the backbone cable is damaged. -Require a terminator at both ends of the cable to stop the signal from bouncing back. -There is a high number of packet losses.

https://firewallfc.com/2023/04/09/bus-topology/

[firewallfc]

Netmiko Script to change history buffer size for current termial session

from netmiko import ConnectHandler net_connect = ConnectHandler(device_type = 'cisco_ios', host='131.226.217.143', username='developer',password ='C1sco12345') output = net_connect.send_command("show terminal | include History") print('Current history buffer ') print(output) print() print('Changing the history buffer size to 9.....') net_connect.send_command("terminal history size 9") output = net_connect.send_command("show terminal | include History") print(output)

[firewallfc]

Creating list from a String and display the elements in reverse order

str  = input('Enter a string: ') strlist= [] print('Length of a string: ',len(str)) for s in str:    strlist.append(s) print(strlist) l = len(strlist) i = -1 revlist =[] while i >= -l:    revlist.append(strlist[i])    i-=1 print(revlist)

[firewallfc]

Pythonping module

Here, we will discuss about the use of pythonping module. This module is used to simply ping the target machine. To install the module, use the command "pip install pythonping". The below example displays a simple code to send ICMP probes to a target machine using the pythonping module. By default, ping runs in silent mode and does not display the result. To display the result, use verbose mode and set the value to True.

from pythonping import ping ping('1.1.1.1', verbose=True)

For examples, click on the link

[firewallfc]

Netmiko script to change interface description

Netmiko python script to change interface description.

from netmiko import ConnectHandler net_connect = ConnectHandler(device_type = 'cisco_ios', host='131.226.217.143', username='developer',password ='C1sco12345') output = net_connect.send_command("show interface description") print(output) command = ['interface Gi2','description Local LAN Interface'] print('Changing description on the interface Gi2') net_connect.send_config_set(command) output = net_connect.send_command("show interface description") print(output)

https://firewallfc.com/network-automation-netmiko-pythn/#Example8

[firewallfc]

Context manager to access Cisco router

Automatically handles opening and closing of the session with a device.

There is no requirement of using the open() and close() method.

from napalm import get_network_driver import json driver = get_network_driver('ios') with driver('131.226.217.143','developer','C1sco12345') as device:    print('Get_facts() method details')    print(json.dumps(device.get_facts(),indent=2))    print()    print('Interface Details')    print(json.dumps(device.get_interfaces_ip(), indent=2))

https://firewallfc.com/2022/10/07/napalm-context-manager-to-connect-to-a-device/

[firewallfc]

NAPALM Script to access a Cisco router

Napalm is a Python library used to perform network automation. It is called unified API and can be used to access network devices with different operating systems. Here, is the simple script to access a device to export its arp entries

from napalm import get_network_driver import json driver = get_network_driver('ios') device = driver('131.226.217.143','developer','C1sco12345') device.open() print(json.dumps(device.get_arp_table(), indent=2)) device.close()

For a complete blog, please visit on below linkhttps://firewallfc.com/2022/10/05/introduction-to-napalm-network-automation/

[firewallfc]

Change hostname of a router | Netmiko script

This blog present overview of changing hostname of a cisco router.

Step 1 : Login into device

Step 2 : Go to configuration mode

Step 3 : Use command hostname actual_hostname

Step 4 : Go back to enable mode and save the configuration

Complete blog post on changing hostnames, including netmiko Python script

https://firewallfc.com/2022/10/12/how-to-change-hostname-of-a-cisco-router/

[firewallfc]

These DIY iPhone Speakers are Genius