pygnmi doesn't send anything over the wire

[akarneliuk]

pygnmi doesn't send anything over the wire

[akarneliuk]

Hello @svautour ,

sorry for the delay, I somehow overlooked your request. I'm afraid you don't provide any details of your setup. Please, provide the configuration of your network device you try to manage with pygnmi.

also, this part is not accurate:

if name == 'main':

It shall be:

if __name__ == "__main__":

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Best,
Anton

[akarneliuk]

Hey @svautour ,

Please, re-open if needed.

Best,
Anton

[svautour]

Re-opening. Sorry for the delay, I was on vacation.

My code does have the underscore. It didn't come across correctly as I didn't paste it as a code block.

What information do you require that I did not include? What command outputs would you like?

The config on the router that I am trying to manage is irrelevant here as when I tcpdump the NIC on the server where I run the code, I see no outbound packets to my device on port 57400.

Thanks for creating and sharing. I am looking forward to a gnmi client for python. I will help if I can.

Serge

[akarneliuk]

Hey @svautour ,

if pygnmi doesn't send anything to a wire, it may be something with your environment. Could you please suggest what is:

• Your OS and its version
• Your Python version
• Output of pip freeze

Best,
Anton

[svautour]

Using a venv:

(virtual3.8) root@xxxxxx-ubuntu:~/TrainingExamples# python3 -V
Python 3.8.0

(virtual3.8) root@xxxxxx-ubuntu:~/TrainingExamples# python3 pygnmitest.py
Traceback (most recent call last):
File "pygnmitest.py", line 7, in
with gNMIclient(target=host, username="svautour", password="xxxxxxx", insecure=True) as gc:
File "/root/TrainingExamples/virtual3.8/lib/python3.8/site-packages/pygnmi/client.py", line 94, in enter
return self.connect()
File "/root/TrainingExamples/virtual3.8/lib/python3.8/site-packages/pygnmi/client.py", line 146, in connect
self.wait_for_connect(timeout)
File "/root/TrainingExamples/virtual3.8/lib/python3.8/site-packages/pygnmi/client.py", line 156, in wait_for_connect
grpc.channel_ready_future(self.__channel).result(timeout=timeout)
File "/root/TrainingExamples/virtual3.8/lib/python3.8/site-packages/grpc/_utilities.py", line 139, in result
self._block(timeout)
File "/root/TrainingExamples/virtual3.8/lib/python3.8/site-packages/grpc/_utilities.py", line 85, in _block
raise grpc.FutureTimeoutError()
grpc.FutureTimeoutError

(virtual3.8) root@xxxxxx-ubuntu:~/TrainingExamples# uname -a
Linux xxxxxx-ubuntu 4.15.0-167-generic #175-Ubuntu SMP Wed Jan 5 01:56:07 UTC 2022 x86_64 x86_64 x86_64 GNU/Linux

(virtual3.8) root@xxxxxx-ubuntu:~/TrainingExamples# more /etc/os-release
NAME="Ubuntu"
VERSION="18.04.5 LTS (Bionic Beaver)"
ID=ubuntu
ID_LIKE=debian
PRETTY_NAME="Ubuntu 18.04.5 LTS"
VERSION_ID="18.04"
HOME_URL="https://www.ubuntu.com/"
SUPPORT_URL="https://help.ubuntu.com/"
BUG_REPORT_URL="https://bugs.launchpad.net/ubuntu/"
PRIVACY_POLICY_URL="https://www.ubuntu.com/legal/terms-and-policies/privacy-policy"
VERSION_CODENAME=bionic
UBUNTU_CODENAME=bionic

(virtual3.8) root@COVEP23tools-ubuntu:~/TrainingExamples# pip3 freeze
cffi==1.15.0
cryptography==36.0.2
dictdiffer==0.9.0
grpcio==1.44.0
grpcio-tools==1.44.0
kthread==0.2.3
protobuf==3.20.0
pycparser==2.21
pygnmi==0.6.9
six==1.16.0

(virtual3.8) root@COVEP23tools-ubuntu:~/TrainingExamples# pip freeze
cffi==1.15.0
cryptography==36.0.2
dictdiffer==0.9.0
grpcio==1.44.0
grpcio-tools==1.44.0
kthread==0.2.3
protobuf==3.20.0
pycparser==2.21
pygnmi==0.6.9
six==1.16.0

Thanks,
Serge

[akarneliuk]

Hey @svautour ,

Try to build a new VM and see how it would work. I've just tested this:

if __name__ == "__main__":
    with gNMIclient(target=(ENV_HOSTNAME, ENV_PORT),
                    username=ENV_USERNAME,
                    password=ENV_PASSWORD,
                    insecure=True) as gconn:
        gconn.capabilities()

        result = gconn.get(path=["/"])
        print(result)

and got:

tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
listening on any, link-type LINUX_SLL (Linux cooked v1), capture size 262144 bytes
16:52:46.668450 IP 192.168.1.115.60630 > ***.***.***.***.57400: Flags [S], seq 2497241027, win 64240, options [mss 1460,sackOK,TS val 867433530 ecr 0,nop,wscale 7], length 0
16:52:46.672539 IP ***.***.***.***.57400 > 192.168.1.115.60630: Flags [S.], seq 1098571442, ack 2497241028, win 65160, options [mss 1460,sackOK,TS val 2456298786 ecr 867433530,nop,wscale 7], length 0
16:52:46.672583 IP 192.168.1.115.60630 > ***.***.***.***.57400: Flags [.], ack 1, win 502, options [nop,nop,TS val 867433534 ecr 2456298786], length 0

So it doesn't seem to be an issue with pygnmi, sir.

Best,
Anton

[svautour]

Hello, I thought I would try this again. Some time has passed and a new version is out. I did a fresh python venv install with python 3.9.12. I also tried pygnmicli instead of pygnmi. I discovered something: (pygnmi-test) ***@***.***_1:~/pygnmi-test# pygnmicli -u test -p test -t 172.16.18.8:57400 -i tcpdump shows no packets sent. However if I remove -i: (pygnmi-test) ***@***.***_1:~/pygnmi-test# pygnmicli -u test -p test -t 172.16.18.8:57400 The SSL certificate cannot be retrieved from ('172.16.18.8', 57400) Traceback (most recent call last): File "/root/pygnmi-test/lib/python3.9/site-packages/pygnmi/client.py", line 145, in connect ssl_cert = ssl.get_server_certificate((self.__target[0], self.__target[1])).encode("utf-8") File "/usr/lib/python3.9/ssl.py", line 1484, in get_server_certificate with context.wrap_socket(sock) as sslsock: File "/usr/lib/python3.9/ssl.py", line 500, in wrap_socket return self.sslsocket_class._create( File "/usr/lib/python3.9/ssl.py", line 1040, in _create self.do_handshake() File "/usr/lib/python3.9/ssl.py", line 1309, in do_handshake self._sslobj.do_handshake() ssl.SSLError: [SSL: WRONG_VERSION_NUMBER] wrong version number (_ssl.c:1129) During handling of the above exception, another exception occurred: Traceback (most recent call last): File "/root/pygnmi-test/bin/pygnmicli", line 165, in <module> main() File "/root/pygnmi-test/bin/pygnmicli", line 39, in main with gNMIclient( File "/root/pygnmi-test/lib/python3.9/site-packages/pygnmi/client.py", line 103, in __enter__ return self.connect() File "/root/pygnmi-test/lib/python3.9/site-packages/pygnmi/client.py", line 149, in connect raise gNMIException(f'The SSL certificate cannot be retrieved from {self.__target}', e) pygnmi.client.gNMIException: The SSL certificate cannot be retrieved from ('172.16.18.8', 57400) and tcpdump shows: ***@***.***_1:~# tcpdump -i ens3 port 57400 -n tcpdump: verbose output suppressed, use -v or -vv for full protocol decode listening on ens3, link-type EN10MB (Ethernet), capture size 262144 bytes 19:38:10.539810 IP 192.168.132.72.49678 > 172.16.18.8.57400: Flags [S], seq 4267049268, win 64240, options [mss 1460,sackOK,TS val 2625562153 ecr 0,nop,wscale 7], length 0 19:38:10.543588 IP 172.16.18.8.57400 > 192.168.132.72.49678: Flags [S.], seq 2140161584, ack 4267049269, win 43440, options [mss 1460,sackOK,TS val 923558734 ecr 2625562153,nop,wscale 11], length 0 19:38:10.543647 IP 192.168.132.72.49678 > 172.16.18.8.57400: Flags [.], ack 1, win 502, options [nop,nop,TS val 2625562156 ecr 923558734], length 0 19:38:10.544100 IP 192.168.132.72.49678 > 172.16.18.8.57400: Flags [P.], seq 1:518, ack 1, win 502, options [nop,nop,TS val 2625562157 ecr 923558734], length 517 19:38:10.547564 IP 172.16.18.8.57400 > 192.168.132.72.49678: Flags [.], ack 518, win 22, options [nop,nop,TS val 923558736 ecr 2625562157], length 0 19:38:10.547590 IP 172.16.18.8.57400 > 192.168.132.72.49678: Flags [P.], seq 1:16, ack 518, win 22, options [nop,nop,TS val 923558736 ecr 2625562157], length 15 19:38:10.547600 IP 192.168.132.72.49678 > 172.16.18.8.57400: Flags [.], ack 16, win 502, options [nop,nop,TS val 2625562160 ecr 923558736], length 0 19:38:10.547617 IP 172.16.18.8.57400 > 192.168.132.72.49678: Flags [R.], seq 16, ack 518, win 22, options [nop,nop,TS val 923558736 ecr 2625562157], length 0 19:38:10.551564 IP 172.16.18.8.57400 > 192.168.132.72.49678: Flags [R], seq 2140161600, win 0, length 0 So whatever part of pygnmi isn't working for me has to do with no TLS "-i" flag. Any suggestions? Thanks, Serge

…

On Sat, Jul 23, 2022 at 2:08 PM Anton Karneliuk ***@***.***> wrote: Hey @svautour <https://github.com/svautour> , Try to build a new VM and see how it would work. I've just tested this: if __name__ == "__main__": with gNMIclient(target=(ENV_HOSTNAME, ENV_PORT), username=ENV_USERNAME, password=ENV_PASSWORD, insecure=True) as gconn: gconn.capabilities() result = gconn.get(path=["/"]) print(result) and got: tcpdump: verbose output suppressed, use -v or -vv for full protocol decode listening on any, link-type LINUX_SLL (Linux cooked v1), capture size 262144 bytes 16:52:46.668450 IP 192.168.1.115.60630 > ***.***.***.***.57400: Flags [S], seq 2497241027, win 64240, options [mss 1460,sackOK,TS val 867433530 ecr 0,nop,wscale 7], length 0 16:52:46.672539 IP ***.***.***.***.57400 > 192.168.1.115.60630: Flags [S.], seq 1098571442, ack 2497241028, win 65160, options [mss 1460,sackOK,TS val 2456298786 ecr 867433530,nop,wscale 7], length 0 16:52:46.672583 IP 192.168.1.115.60630 > ***.***.***.***.57400: Flags [.], ack 1, win 502, options [nop,nop,TS val 867433534 ecr 2456298786], length 0 So it doesn't seem to be an issue with pygnmi, sir. Best, Anton — Reply to this email directly, view it on GitHub <#57 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/ADLZ2VMNCCXVFWME7KFYKRTVVQRINANCNFSM5UL7ADDQ> . You are receiving this because you were mentioned.Message ID: ***@***.***>

[jbemmel]

If this is against SR Linux (or perhaps some other device with security by default), try insecure=False