任意のRTに任意のコマンドを実行して結果を出力するスクリプト
スクリプト
from netmiko import ConnectHandler
from netmiko import NetMikoAuthenticationException
from netmiko import NetMikoTimeoutException
import getpass
Routers = {
"R19" : "192.168.122.19",
"R20" : "192.168.122.20",
"R21" : "192.168.122.21",
"R29" : "192.168.122.29",
"R30" : "192.168.122.30",
"R31" : "192.168.122.31"
}
ipaddr = input("Which router do you want to connect?\navailable router: R19, R20, R21, R29, R30, R31\n: ")
router = Routers.get(ipaddr, f"{ipaddr} does not exist")
for i in router:
if router == f"{ipaddr} does not exist":
print("\n",router)
ipaddr = input("Which router do you want to connect?\navailable router: R19, R20, R21, R29, R30, R31\n: ")
router = Routers.get(ipaddr, f"{ipaddr} does not exist")
uname = input("Please enter your Username: ")
passwd = getpass.getpass("Please enter your Password: ")
cmd = input("Please enter the command you want to execute: ")
Router = ConnectHandler(ip = router, username = uname, password = passwd, device_type = "cisco_xe")
def rtr_function(dev):
dev.send_command("terminal length 0")
hostname = dev.send_command("show run | in hostname").split()[1]
print(f"*****The result of `{cmd}` on {hostname}*****")
print("\n")
result = dev.send_command(cmd)
print(result)
print("\n")
dev.disconnect()
try:
rtr_function(Router)
except(NetMikoAuthenticationException):
print("Authentication Failure")
except(NetMikoTimeoutException):
print(f"Connecting to {router} Time out")こだわりポイント
・前回の反省で挙げていた、想定外のルータが指定されたときに入力し直させ、正しい値が入力するまで繰り返させる動作を実装した
出力例
root@*****# python3 output.py
Which router do you want to connect?
available router: R19, R20, R21, R29, R30, R31
: R2
R2 does not exist
Which router do you want to connect?
available router: R19, R20, R21, R29, R30, R31
: R6
R6 does not exist
Which router do you want to connect?
available router: R19, R20, R21, R29, R30, R31
: adsljfaldjsf
adsljfaldjsf does not exist
Which router do you want to connect?
available router: R19, R20, R21, R29, R30, R31
: R19
Please enter your Username: admin
Please enter your Password:
Please enter the command you want to execute: show ip int bri
*****The result of `show ip int bri` on R19*****
Interface IP-Address OK? Method Status Protocol
GigabitEthernet0/0 10.19.21.19 YES NVRAM up up
GigabitEthernet0/1 10.19.29.19 YES NVRAM up up
GigabitEthernet0/2 10.19.20.19 YES NVRAM up up
GigabitEthernet0/3 unassigned YES NVRAM administratively down down
GigabitEthernet0/4 unassigned YES NVRAM administratively down down
GigabitEthernet0/5 100.3.19.19 YES NVRAM up up
GigabitEthernet0/6 100.6.19.19 YES NVRAM up up
GigabitEthernet0/7 unassigned YES NVRAM administratively down down
Loopback0 150.19.19.19 YES NVRAM up up
root@*****#
次回に向けて
①ipaddr = input("Which router do you want to connect?\navailable router: R19, R20, R21, R29, R30, R31\n: ")
②router = Routers.get(ipaddr, f"{ipaddr} does not exist")
・上記２文を全く同じ形で２回使っているのが気持ち悪い。どうにかしたい。
・ConnectHandler()を使用中にSSHのパスワードがミスマッチすると、Pythonスクリプトのエラーログを返す。おそらく、.establish_connection()に代替すれば解決すると思うのでそれを実装したい
root@*****# python3 output.py
Which router do you want to connect?
available router: R19, R20, R21, R29, R30, R31
: R19
Please enter your Username: admin
Please enter your Password:
Please enter the command you want to execute: show ip int bri
Traceback (most recent call last):
File "/usr/lib/python3/dist-packages/netmiko/base_connection.py", line 884, in establish_connection
self.remote_conn_pre.connect(**ssh_connect_params)
File "/usr/lib/python3/dist-packages/paramiko/client.py", line 435, in connect
self._auth(
File "/usr/lib/python3/dist-packages/paramiko/client.py", line 764, in _auth
raise saved_exception
File "/usr/lib/python3/dist-packages/paramiko/client.py", line 751, in _auth
self._transport.auth_password(username, password)
File "/usr/lib/python3/dist-packages/paramiko/transport.py", line 1509, in auth_password
return self.auth_handler.wait_for_response(my_event)
File "/usr/lib/python3/dist-packages/paramiko/auth_handler.py", line 250, in wait_for_response
raise e
paramiko.ssh_exception.AuthenticationException: Authentication failed.
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
File "output.py", line 28, in <module>
Router = ConnectHandler(ip = router, username = uname, password = passwd, device_type = "cisco_xe")
File "/usr/lib/python3/dist-packages/netmiko/ssh_dispatcher.py", line 246, in ConnectHandler
return ConnectionClass(*args, **kwargs)
File "/usr/lib/python3/dist-packages/netmiko/base_connection.py", line 317, in __init__
self._open()
File "/usr/lib/python3/dist-packages/netmiko/base_connection.py", line 322, in _open
self.establish_connection()
File "/usr/lib/python3/dist-packages/netmiko/base_connection.py", line 897, in establish_connection
raise NetMikoAuthenticationException(msg)
netmiko.ssh_exception.NetMikoAuthenticationException: Authentication failure: unable to connect cisco_xe 192.168.122.19:22
Authentication failed.
root@*****#
うまいこといかないことも多々あるけど楽しすぎる。