1. Multi-Device SSH Automation

Connect to multiple routers/switches simultaneously to send command sets using Netmiko.

from netmiko import ConnectHandler

devices = [
    {"device_type": "cisco_ios", "host": "192.168.1.10", "username": "admin", "password": "password"},
    {"device_type": "cisco_ios", "host": "192.168.1.11", "username": "admin", "password": "password"}
]

for device in devices:
    print(f"
Connecting to {device['host']}...")
    try:
        connection = ConnectHandler(**device)
        output = connection.send_command("show ip interface brief")
        print(output)
        connection.disconnect()
    except Exception as e:
        print(f"Failed to connect to {device['host']}: {e}")

2. Automatic Configuration Backup

Pull running configurations from network elements and save them locally with timestamped filenames.

from netmiko import ConnectHandler
from datetime import datetime
from pathlib import Path

device = {"device_type": "cisco_ios", "host": "192.168.1.10", "username": "admin", "password": "password"}
backup_dir = Path("network_backups")
backup_dir.mkdir(exist_ok=True)

connection = ConnectHandler(**device)
config = connection.send_command("show running-config")
filename = backup_dir / f"{device['host']}_{datetime.now():%Y%m%d_%H%M%S}.cfg"
filename.write_text(config)

print(f"Backup saved: {filename}")
connection.disconnect()

3. Interface Health & Status Checker

Audit interfaces across network elements to detect down links or err-disabled ports.

from netmiko import ConnectHandler

device = {"device_type": "cisco_ios", "host": "192.168.1.10", "username": "admin", "password": "password"}
connection = ConnectHandler(**device)
output = connection.send_command("show interfaces status", use_textfsm=True)

for intf in output:
    if intf.get('status') in ['notconnect', 'err-disabled', 'disabled']:
        print(f"Alert: Interface {intf.get('port')} status: {intf.get('status')}")

connection.disconnect()

4. CSV-Based Device Inventory Automation

Iterate through external inventory source files (CSV) and bulk-execute network queries.

import csv
from netmiko import ConnectHandler

with open("devices.csv") as file:
    for device in csv.DictReader(file):
        print(f"Connecting to {device['host']}...")
        connection = ConnectHandler(**device)
        print(connection.send_command("show version")[:300])
        connection.disconnect()

5. Multi-Switch VLAN Provisioning

Push structured VLAN changes to switches, verify output, and write changes to memory.

from netmiko import ConnectHandler

switches = [
    {"device_type": "cisco_ios", "host": "192.168.1.10", "username": "admin", "password": "password"},
    {"device_type": "cisco_ios", "host": "192.168.1.11", "username": "admin", "password": "password"}
]

commands = ["vlan 100", "name SERVERS_ZONE"]

for switch in switches:
    connection = ConnectHandler(**switch)
    print(connection.send_config_set(commands))
    connection.save_config()
    connection.disconnect()

6. Templated Configuration Generation (Jinja2)

Generates standardized Cisco IOS configurations from variables using Jinja2 templates.

from jinja2 import Template

template_str = """
hostname {{ hostname }}
interface {{ interface }}
 description {{ description }}
 ip address {{ ip_address }} {{ subnet_mask }}
 no shutdown
"""

data = {
    "hostname": "C9300-DIST-01",
    "interface": "GigabitEthernet1/0/1",
    "description": "Uplink to Core Router",
    "ip_address": "10.0.10.1",
    "subnet_mask": "255.255.255.252"
}

print(Template(template_str).render(data))

7. Concurrent Reachability Monitor

Tests IP reachability across subnets or device inventory concurrently.

import subprocess
from concurrent.futures import ThreadPoolExecutor

devices = ["192.168.1.1", "192.168.1.10", "192.168.1.11", "10.0.0.1"]

def ping(ip):
    res = subprocess.run(["ping", "-n", "2", ip], stdout=subprocess.DEVNULL)
    return f"{ip} : {'UP' if res.returncode == 0 else 'DOWN'}"

with ThreadPoolExecutor(max_workers=4) as executor:
    for result in executor.map(ping, devices):
        print(result)

8. CPU & Memory Utilization Monitor

Extracts system resource metrics and triggers alerts for high utilization.

import re
from netmiko import ConnectHandler

device = {"device_type": "cisco_ios", "host": "192.168.1.10", "username": "admin", "password": "password"}
connection = ConnectHandler(**device)
output = connection.send_command("show processes cpu | include CPU utilization")
connection.disconnect()

match = re.search(r"five minutes:\s*(\d+)%", output)
if match:
    cpu = int(match.group(1))
    print(f"Device: {device['host']} | CPU: {cpu}% | Status: {'HIGH' if cpu > 80 else 'NORMAL'}")

9. Configuration Compliance Auditor

Checks if running configurations comply with security baseline standards.

import re
from netmiko import ConnectHandler

checks = {
    "AAA Model": r"aaa new-model",
    "SSH v2": r"ip ssh version 2",
    "HTTP Disabled": r"no ip http server"
}

device = {"device_type": "cisco_ios", "host": "192.168.1.10", "username": "admin", "password": "password"}
connection = ConnectHandler(**device)
config = connection.send_command("show running-config")
connection.disconnect()

for name, pattern in checks.items():
    status = "PASS" if re.search(pattern, config) else "FAIL"
    print(f"{name:<20} : {status}")

10. Automated Network Health Report Generator

Aggregates reachability, interface health, resources, and baseline compliance into a report.

import pandas as pd

summary = {
    "Metric": ["Devices Up", "Devices Down", "Interfaces Up", "High CPU Warnings"],
    "Count": [24, 1, 186, 3],
    "Status": ["OK", "ALERT", "OK", "WARN"]
}

df = pd.DataFrame(summary)
df.to_html("network_health_report.html", index=False)
df.to_excel("network_health_report.xlsx", index=False)
print("Health reports generated successfully.")