Invalid output from MD5 command

[veerar77]

HI, please help me. i am using router C3660-A3JK9S-M on GNS3 and getting the below error.

import json
from napalm import get_network_driver
v = get_network_driver("ios")
enable = {"secret": "\n"}
conn = v(hostname="192.168.226.138", username="Veera", password="Veera556_",optional_args=enable)
conn.open()
conn.load_merge_candidate(filename="commands.txt")
conn.commit_config()
out = conn.get_interfaces_ip()
out1 = json.dumps(out, indent=4)
print(out1)
conn.close()

output:

Traceback (most recent call last):
File "C:\Users\avita\PycharmProjects\pythonProject\Napalm\test.py", line 9, in
conn.load_merge_candidate(filename="commands.txt")
File "C:\Users\avita\PycharmProjects\pythonProject\venv\Lib\site-packages\napalm\ios\ios.py", line 317, in load_merge_candidate
return_status, msg = self._load_candidate_wrapper(
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "C:\Users\avita\PycharmProjects\pythonProject\venv\Lib\site-packages\napalm\ios\ios.py", line 284, in _load_candidate_wrapper
(return_status, msg) = self._scp_file(
^^^^^^^^^^^^^^^
File "C:\Users\avita\PycharmProjects\pythonProject\venv\Lib\site-packages\napalm\ios\ios.py", line 733, in _scp_file
return self._xfer_file(
^^^^^^^^^^^^^^^^
File "C:\Users\avita\PycharmProjects\pythonProject\venv\Lib\site-packages\napalm\ios\ios.py", line 808, in _xfer_file
if transfer.verify_file():
^^^^^^^^^^^^^^^^^^^^^^
File "C:\Users\avita\PycharmProjects\pythonProject\venv\Lib\site-packages\netmiko\scp_handler.py", line 413, in verify_file
return self.compare_md5()
^^^^^^^^^^^^^^^^^^
File "C:\Users\avita\PycharmProjects\pythonProject\venv\Lib\site-packages\netmiko\scp_handler.py", line 364, in compare_md5
remote_md5 = self.remote_md5()
^^^^^^^^^^^^^^^^^
File "C:\Users\avita\PycharmProjects\pythonProject\venv\Lib\site-packages\netmiko\scp_handler.py", line 386, in remote_md5
dest_md5 = self.process_md5(dest_md5)
^^^^^^^^^^^^^^^^^^^^^^^^^^
File "C:\Users\avita\PycharmProjects\pythonProject\venv\Lib\site-packages\netmiko\scp_handler.py", line 359, in process_md5
raise ValueError(f"Invalid output from MD5 command: {md5_output}")
ValueError: Invalid output from MD5 command: %Error computing MD5 hash flash:/merge_config.txt (No such file or directory)

on Router:

Veera1#sh flash:

System flash directory:
File Length Name/status
1 101 merge_config.txt [deleted]
2 59 merge_config.txt [deleted]
3 59 merge_config.txt [invalid checksum]
[416 bytes used, 7863900 available, 7864316 total]
8192K bytes of processor board System flash (Read/Write)

Veera1#erase flash:
Erasing the flash filesystem will remove all files! Continue? [confirm]
Erasing device... eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee ...erased

Veera1#sh flash:

System flash directory:
No files in System flash
[0 bytes used, 7864316 available, 7864316 total]
8192K bytes of processor board System flash (Read/Write)

getting the same first flash output when i run the script again.

i am using napalm 4.0.0, netmiko 4.1.2

[ktbyers]

You probably should capture the Netmiko session log to see what is going on.

NAPALM/Netmiko is expecting there to be a valid merge_config.txt file in your flash file system.

    def remote_md5(
        self, base_cmd: str = "verify /md5", remote_file: Optional[str] = None
    ) -> str:
        """Calculate remote MD5 and returns the hash.

        This command can be CPU intensive on the remote device.
        """
        if remote_file is None:
            if self.direction == "put":
                remote_file = self.dest_file
            elif self.direction == "get":
                remote_file = self.source_file
        remote_md5_cmd = f"{base_cmd} {self.file_system}/{remote_file}"
        dest_md5 = self.ssh_ctl_chan._send_command_str(remote_md5_cmd, read_timeout=300)

So it is expecting to execute a and have it look similar to:

cisco5#verify /md5 flash:merge_config.txt
Done!
verify /md5 (bootflash:merge_config.txt) = d41d8cd98f00b204e9800998ecf8427e

[veerar77]

Hello @ktbyers , thanks for the quick response.

there wasn't any file with the name of merge_config.txt in the flash or disk.

the flash was initially empty. However, when i run the script it created and deleted the merge_config.txt in flash.

Veera1#sh flash:

System flash directory:
File Length Name/status
1 59 merge_config.txt [deleted]
2 59 merge_config.txt [deleted]
[248 bytes used, 8388356 available, 8388604 total]
8192K bytes of processor board System flash (Read/Write)

Veera1#verify /md5 flash: ?
WORD Expected md5 signature

can you guide me how to capture the Netmiko session log? i am using pycharm IDE.

do you any suggestion about proper IOS image should use on GNS3?

[ktbyers]

Stop your program before NAPALM deletes the file (or don't call .close() ).

Add a session_log: "output.txt", argument into NAPALM's optional_args dictionary. This should create a file named 'output.txt' in the directory you run NAPALM from.

[veerar77]

@ktbyers thank you so much for your suggestions.

i followed the same but had no luck. however, i got the right working vIOS imageand tested.

For GNS3 , EVE-NG & pnetlab we should use the IOS version image " vios-adventerprisek9-m.vmdk.SPA.156-2.T.qcow2 ".

[ktbyers]

I suspect it probably has something to do with the file-system on these virtual devices (for future people looking at this issue).