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MySQL (MariaDB) [WinError 10053] An established connection was aborted by the software in your host machine

So, I'm struggling with mysql
I tried to use mysql.connector, though it turned out that it doesn't really want to cooperate when I'm connecting via sshtunnel
So I transfered to pymysql, and here's the most basic code I was able to write:
import pymysql
from sshtunnel import SSHTunnelForwarder
with SSHTunnelForwarder(('192.168.0.x', 22), ssh_username='pi', ssh_password='*********', remote_bind_address=('localhost', 3306)) as tunnel:
tunnel.start()
mydb = pymysql.connect(host="localhost",
user='Mashu',
passwd='******',
port=tunnel.local_bind_port,
db='Special_Channels')
print(mydb)
query = "SELECT * FROM Daily"
cur = mydb.cursor()
data = cur.execute(query)
print(data)
Though on
cur = mydb.cursor()
it raises an error:
ConnectionAbortedError: [WinError 10053] An established connection was aborted by the software in your host machine
Also on a higher level it is:
pymysql.err.OperationalError: (2013, 'Lost connection to MySQL server during query ([WinError 10053] An established connection was aborted by the software in your host machine)')
I'm sure the database and table existst, and that this mysql account is accessible, as I have it opened and made changes to it in other software (DataGrip if anyone wonders)

I suggest mariadb instead of pymysql for your case
pip install mariadb

Solution is pretty easy.
it should all be inside with statement as tunnel connection (therefore database access) is closed outside statement, so it should look like this:
import pymysql
from sshtunnel import SSHTunnelForwarder
with SSHTunnelForwarder(('192.168.0.x', 22), ssh_username='pi', ssh_password='*********', remote_bind_address=('localhost', 3306)) as tunnel:
tunnel.start()
mydb = pymysql.connect(host="localhost",
user='Mashu',
passwd='******',
port=tunnel.local_bind_port,
db='Special_Channels')
print(mydb)
query = "SELECT * FROM Daily"
cur = mydb.cursor()
data = cur.execute(query)
print(data)

Can't SSH to Google Cloud Compute Engine with sshtunnel

I prepared two VM instance with Compute Engine on GCP.
ServerA: Data processing and read/write to SQL(mysql) on ServerB.
ServerB: SQL Server (f1-micro* This is not Cloud SQL, but normal VM instance.)
Trying to access SSH from A to B in order to read/write DB on ServerB with the code below.
error code
error: ERROR | Problem setting SSH Forwarder up: Couldn't open tunnel localhost:3306 <> localhost:3306 might be in use or destination not reachable
sshtunnel.HandlerSSHTunnelForwarderError: An error occurred while opening tunnels.
#SSH connection
with SSHTunnelForwarder(
('PublicIP of ServerA', 22),
ssh_pkey=SSH_PKEY_PATH,
ssh_username=SSH_USER,
remote_bind_address=('localhost', 3306),
local_bind_address=('localhost', 3306)
) as ssh:
try:
#DB connection
connection = mysql.connector.connect(
host='localhost',
port = 3306,
user=MYSQL_USER,
passwd=MYSQL_PASS,
db=MYSQL_DB,
charset='utf8'
)
# print(connection.is_connected())
# Get Cur
cur = connection.cursor()
sql = "use dbname"
cur.execute(sql)
for i in range(len(sqlList)):
print("DB Access：" + str(sqlList[i]))
sql = str(sqlList[i])
# sql = 'create table test (id int, content varchar(32))'
cur.execute(sql)
sqlOUTPUT = cur.fetchall()
# rows = cur.fetchall()
# for row in rows:
# print(row)
except mysql.connector.Error as err:
print("Something went wrong: {}".format(err))
connection.rollback()
raise err
finally:
#Cur close
cur.close()
# Commit
connection.commit()
#DB Connection close
connection.close()
return sqlOUTPUT
But after "local_bind_address=(localhost, MYSQL_PORT)", an error occurs despite it goes through with the same code and same private key on the shell of B or on VSCode local environment.
I don't understand why it goes through with same code using shell and VSCode although it doesn't work on GCE.
Any help?

You might be able to debug this further and discard any issues with sshtunnel if you try to create the tunnel outside of the script from the client VM, with:
$ gcloud compute ssh server-a --zone=your-zone --ssh-flag='-NL 3306:127.0.0.1:3306' &
Then attempt a connection with:
$ mysql -h 127.0.0.1

Connect to MySQL on GCE using Google Colaboratory

I am trying to access MySQL on GCE VM instance through Google Colaboratory though, unfortunately, it does not work properly but does work in the local VSCode environment.
While executing TestExec.py, it shows SSH Connected so it seems that ssh connection is successfully done though, however, it seems to be stuck on MySQL connection.
Output on Google Colab:
Please help with the solutions/tips?
sqlList = []
sqlList.append("select * from table name;")
HOST = 'ComputeEngine PublicIP'
PORT = 22
USER = 'username'
DBUSER = 'username for db'
KEY_FILE = 'private key file path'
DBNAME = 'dbname'
DBPORT = 3306
SSH_BASTION_ADDRESS = HOST
SSH_PORT = PORT
SSH_USER = USER
SSH_PKEY_PATH = KEY_FILE
MYSQL_HOST = HOST
MYSQL_PORT = 3306
MYSQL_USER = DBUSER
MYSQL_PASS = 'MySQL Login PW'
MYSQL_DB = DBNAME
with SSHTunnelForwarder(
(SSH_BASTION_ADDRESS, SSH_PORT),
ssh_pkey=SSH_PKEY_PATH,
ssh_username=SSH_USER,
# ssh_password=PASSPHRASE,
remote_bind_address=('localhost', MYSQL_PORT),
local_bind_address=('localhost', MYSQL_PORT)
) as ssh:
print("SSH Connected")
print(ssh.local_bind_port)
try:
connection = mysql.connector.connect(
host='localhost',
port = ssh.local_bind_port,
user=MYSQL_USER,
passwd=MYSQL_PASS,
db=MYSQL_DB,
charset='utf8'
)
print(connection.is_connected())
print("DB Connected")
cur = connection.cursor()
sql = "use dbname"
cur.execute(sql)
# rows = cur.fetchall()
# for row in rows:
# print(row)
for i in range(len(sqlList)):
print(sqlList[i])
sql = str(sqlList[i])
# sql = 'create table test (id int, content varchar(32))'
cur.execute(sql)
rows = cur.fetchall()
for row in rows:
print(row)
except mysql.connector.Error as err:
print("Something went wrong: {}".format(err))
connection.rollback()
raise err
finally:
cur.close()
connection.commit()
connection.close()

It seemed the error occurred because of the connection. I have changed the method of connection.
import pymysql.cursors
connection = pymysql.connect(
host='localhost',
user='user',
password='password!',
db='dbname',
charset='utf8mb4',
cursorclass=pymysql.cursors.DictCursor
)

PyMySQL using localhost vs socket incoherant behaviour

I am using PyMySQL to connect to a database running on localhost. I can access the database just fine using the username/password combiunation in both the command line and adminer so the database does not appear to be the probem here.
My code is as follow. However, when using the host="127.0.0.1" options, I get an OperationalError and an Errno 111. Using the same code, but connecting via the socket Mariadb runs on is fine.
import pymysql.cursors
from pprint import pprint
# This causes an OperationalError: (pymysql.err.OperationalError) (2003, "Can't connect to MySQL server on 'localhost' ([Errno 111] Connection refused)")
# connection = pymysql.connect(
# host="127.0.0.1",
# port=3306,
# user="root",
# password="S3kr37",
# db="my_test",
# )
# This works.
connection = pymysql.connect(
user="root",
password="S3kr37",
db="my_test",
unix_socket="/var/lib/mysql/mysql.sock"
)
try:
with connection.cursor() as cursor:
sql = "select * from MySuperTable"
cursor.execute(sql)
results = cursor.fetchall()
pprint(results)
finally:
connection.close()
What am I doing wrong?
PS: Note that this question has the same problem but the solution offered is the socket. That is no good enough: I want to know why I cannot use the hostname as the documentation suggests.

Errorcode 2003 (CR_CONN_HOST_ERROR) is returned by the client library, in case the client wasn't able to establish a tcp connection to the server.
First you should check, if you can connect via telnet or mysql command line client to your server.
If not, check the server configuration file:
does the server run on port 3306?
is IPv4 disabled?
is skip-networking enabled?
is bind-address activated (with another IP?

MySQL remote query works, but remote insert fails via Python

I'm running Ubuntu 16.04 with MySQL. I've opened the MySQL server for remote connections, and my remote Python script can query my database, but all attempts to INSERT fail without any error log entry.
It also looks like my remote INSERTs are being seen, because my AUTO_INCREMENT ID increases without entries being made when I run the Python INSERT code.
Any insight is appreciated!
Simple table schema:
CREATE TABLE test (
ID int NOT NULL AUTO_INCREMENT,
x INT,
PRIMARY KEY (ID)
);
This works directly on the server:
INSERT INTO test (x) VALUES (10);
This is the Python query that's working:
try:
connection = db.Connection(host=HOST, port=PORT, user=USER, passwd=PASSWORD, db=DB)
cursor = connection.cursor()
print("Connected to Server")
cursor.execute("SELECT * FROM test")
result = cursor.fetchall()
for item in result:
print(item)
except Exception as e:
print('exception connecting to server db: ' + str(e))
finally:
print('closing connection...')
connection.close()
And the Python INSERT that's not working:
try:
connection = db.Connection(host=HOST, port=PORT, user=USER, passwd=PASSWORD, db=DB)
cursor = connection.cursor()
print("Connected to Server")
cursor.execute("INSERT INTO test (x) VALUES (10);")
except Exception as e:
print('exception connecting to server db: ' + str(e))
finally:
print('closing connection...')
connection.close()
Thanks

Add this line after the execute() call:
cursor.execute("INSERT INTO test (x) VALUES (10)")
connection.commit()
When making changes to the db, it is required that you commit your changes, no change(s) would take effect.