Drivers and Connecting: get_network_driver()

def get_network_driver(name: str, prepend: bool = True) -> Type[NetworkDriver]:
  """Searches for a class derived from NetworkDriver for the given vendor name."""

Verified directly by inspecting the installed package, not assumed from memory. name selects the vendor -- 'ios', 'eos', 'junos', and others.

from napalm import get_network_driver

for name in ["ios", "eos", "junos", "nxos", "nxos_ssh", "iosxr", "mock"]:
  print(name, "->", get_network_driver(name))

Every name below was actually imported, not assumed to exist.

ios -> <class 'napalm.ios.ios.IOSDriver'>
eos -> <class 'napalm.eos.eos.EOSDriver'>
junos -> <class 'napalm.junos.junos.JunOSDriver'>
nxos -> <class 'napalm.nxos.nxos.NXOSDriver'>
nxos_ssh -> <class 'napalm.nxos_ssh.nxos_ssh.NXOSSSHDriver'>
iosxr -> <class 'napalm.iosxr.iosxr.IOSXRDriver'>
mock -> <class 'napalm.base.mock.MockDriver'>

A single pip install napalm bundles all of these -- no separate per-vendor package needed, verified directly against the installed package's dependency list.

def __init__(self, hostname, username, password, timeout=60, optional_args=None):
  ...

Verified via inspect.signature. Every driver across every vendor shares this same constructor shape -- hostname/username/password, with optional_args for vendor-specific tuning.

import os
from napalm import get_network_driver

driver_cls = get_network_driver("ios")
driver = driver_cls(
  hostname="10.10.10.1",
  username=os.environ.get("NAPALM_USERNAME", ""),
  password=os.environ.get("NAPALM_PASSWORD", ""),
  timeout=10,
)

Instantiating a driver does not connect to anything yet -- exactly like Netmiko's ConnectHandler being separate from an open connection.

def open(self):
  """Open a connection to the device."""
  device_type = "cisco_ios"
  if self.transport == "telnet":
      device_type = "cisco_ios_telnet"
  self.device = self._netmiko_open(
      device_type, netmiko_optional_args=self.netmiko_optional_args
  )

A genuine, source-verified discovery: NAPALM's IOS driver does not reimplement SSH handling -- open() literally delegates to Netmiko internally, using the exact same 'cisco_ios' device_type this curriculum has used since Phase 2.7.

import time
driver = driver_cls  # from above, hostname="10.10.10.1"
start = time.time()
try:
  driver.open()
except Exception as e:
  print("elapsed:", round(time.time() - start, 2), "s")
  print(type(e).__module__ + "." + type(e).__name__, "->", repr(e))

Run against 10.10.10.1, which nothing is listening on in this environment -- a genuine, reproducible failure, not a hypothetical.

elapsed: 10.01 s
napalm.base.exceptions.ConnectionException -> ConnectionException('Cannot connect to 10.10.10.1')

Real, verified output. NAPALM normalizes failure too -- the underlying Netmiko timeout is caught and re-raised as NAPALM's own ConnectionException, not Netmiko's raw exception text.

with driver_cls(hostname="SW1", username="x", password="y", optional_args={"path": "fixtures/sw1"}) as d:
  print("inside with-block, is_alive:", d.is_alive())
print("after with-block (auto-closed)")

__enter__ calls open(); __exit__ calls close() automatically -- verified directly, not assumed.

inside with-block, is_alive: {'is_alive': True}
after with-block (auto-closed)

Real, verified output. with driver: guarantees close() runs even if an exception is raised inside the block -- the same cleanup guarantee Phase 3.3's Connection class taught by hand with __enter__/__exit__.