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Connection to remote mysql server through ssh using python mysqldb connector passwordless

Python 3.8
Mysql 8.0.23-0ubuntu0.20.04.1 for Linux on x86_64 ((Ubuntu))
Hi,
I want to connect to a distant mysql server using python's mysqldb connector and paramiko's sshtunnelforwarder.
I can connect to the database remotely without any problems by executing the following:
Connecting to database using mysql password authentication
server = new_ssh_server(config)
with server:
print('Connection', server.local_bind_address)
cnx = MySQLdb.connect(host = '127.0.0.1',
port = server.local_bind_port,
user = config['user'],
passwd = config['password'],
db = config['db'])
Queries work, I can read/write to database, no problem.
I would like to connect to database without supplying mysql password, by using mysql auth_socket authentication method, through ssh.
My attempts at this can be resumed by the following code:
Connecting to database using mysql auth_socket authentication
with server as tunnel:
print('Tunnel:', tunnel.local_bind_address)
cnx = MySQLdb.connect(host = 'localhost', user = 'hillbilly', password = '', db='tutut')#, unix_socket="/tmp/mysql.sock")
res = pd.read_sql('select * from users;', cnx)
print(res)
Which throws the following error:
File "connect_ssh_mysql_auth_socket.py", line 12, in <module>
cnx = MySQLdb.connect(host = 'localhost', user = 'hillbilly', password = '', db='rsotest2')#, unix_socket="/tmp/mysql.sock")
File "...../lib/python3.8/site-packages/MySQLdb/__init__.py", line 84, in Connect
return Connection(*args, **kwargs)
File "...../lib/python3.8/site-packages/MySQLdb/connections.py", line 179, in __init__
super(Connection, self).__init__(*args, **kwargs2)
MySQLdb._exceptions.OperationalError: (2002, "Can't connect to local MySQL server through socket '/tmp/mysql.sock' (2)")
I have and existing mysqld.sock on the distant server that I symlinked to /tmp/mysql.sock, but the error remains. I have also added the next line to /etc/mysql/mysql.conf.d/mysql.cnf:
socket=/run/mysqld/mysqld.sock
But I still get the same error when trying to connect remotely.
Specifying the unix_socket='/run/mysqld/mysqld.sock' to mysqldb connector (commented in Connecting to database using mysql auth_socket authentication) does not fix the issue.
I seem to misunderstand the use of mysql.sock, mysqld.sock.
I was not able to find nor create a mysql.sock socket.
Is what I am trying to do possible? I remember reading somewhere that unix sockets only work locally, does this mean it is not achievable?
Any help/explanation would be appreciated.
(EDIT AND CLOSING)
So this is not possible. Following this thread, auth_socket needs local access to the socket file (usually /tmp/mysql.sock) to run autentication tests, so not accessible through ssh tunneling.

Authentication to remote mysql server using auth_socket plugin is not possible through sshtunnel, as the plugin requires local access to the socket file. See this thread for more information.

Connecting to MYSQL AWS-RDS using SQLAlchemy in Pycharm/ with Python

Click to see RDS settings
Im trying to connect to a MYSQL server on Amazons Web Service, specifically the RDS- using SQLAlchemy in python (Pycharm).
I've already installed drivers for pymysql to include in the connection string for the engine (engine = create_engine("mysql+pymysql://...).
I've tried setting the CIDR security group inbound and outbound rules to allow any IP.
I can connect to the AWS-RDS just fine from MYSQL Workbench suing the Endpoint, Port and credentials.
I was able to connect to a local instance of MYSQL using SQLAlchemy and create_engine(...) without any issues too.
I've tried including and excluding the port from the URL.
try: # exception handling for database creation/ existence
engine = create_engine(link_to_db, pool_pre_ping=True, pool_recycle=3600) # Access the DB Engine
connection = engine.connect()
print("Database conn 1 successful")
except Exception as e:
logging.exception(e)
print("error connecting to db")
where link_to_db is "mysql+pymysql://{RDS USERNAME}:{RDS PASSWORD}#
{RDS ENDPOINT}:3306/{DATABASE NAME}"
The expected result is
"Database conn 1 successful"
printed to the output.
Errors :
sqlalchemy.exc.OperationalError: (pymysql.err.OperationalError) (2003, "Can't connect to MySQL server on '{RDS URL}' ([Errno 11001] getaddrinfo failed)")
(Background on this error at: http://sqlalche.me/e/e3q8)

Kindly check the below things.
1) Check your rds is publicly accessible to YES. if its in private subnet check connectivity between your source(office/home/etc) to destination(RDS).
2) open 3306 in the security group.
3) check master user credentials.
# telnet {rds end-point} 3306

I found that it was as simple as changing from a multiline string """ {link} """ to single quotes '{link}'.

Connecting to local SQL Server instance

I'm attempting to connect to a local instance of SQL Server running on my machine. I am able to connect to a local instance with this code from our server, but it fails on my local machine.
I've enabled named pipes and all the ips in the SQL Server configuration.
The code I'm using is as follows:
from pymssql import connect
server = r'.\SQLEXPRESS2014' # I've also tried MORGANT-PC\SQLEXPRESS and SQLEXPRESS2014
username = 'MyUserName'
password = 'MyPassword'
master_database_name = 'SuperSecretDatabase'
port = 5000
server_args = {'host': server, 'user': username, 'password': password,
'database': master_database_name, 'port': port} # I've tried having the first key be both host and server, because pymssql's docs are unclear on the difference.
master_database = connect(**server_args)
If I use the instance name, I get this error:
pymssql.InterfaceError: Connection to the database failed for an unknown reason.
I set the port to 5000 so that I could try connecting to it with
server = 127.0.0.1
port = 5000
which fails with the slightly different error message:
pymssql.OperationalError: (20009, b'DB-Lib error message 20009, severity 9:\nUnable to connect: Adaptive Server is unavailable or does not exist\nNet-Lib error during Unknown error (10035)\n')
I've read a bunch of answers here on SO, and most of them seem to indicate it's an issue with FreeTDS, but I'm on Windows 8.1, so I don't have FreeTDS.
I've tried connecting with sqlcmd with the host\instance name and that works fine. It also works in SSMS.
I've tried passing .\SQLEXPRESS2014 to both the host and server parameter in pymssql.connect() and they both fail with the same aforementioned error.
I briefly tried using adodbapi, but I'm getting exactly the same error messages.

The solution ended up being a combination of things.
I needed to disable all IPs other than 127.0.0.1.
I needed to create C:\freetds.conf with the following text:
[global]
port = 1433
tds version = 7.0
I needed to change the account my SQL instance logs in with to LocalSystem.

Yes, 1433 s the default.
This works fine for me:
library(RODBC)
dbconnection <- odbcDriverConnect("Driver=ODBC Driver 11 for SQL Server;Server=server_name; Database=db_name;Uid=; Pwd=; trusted_connection=yes")
initdata <- sqlQuery(dbconnection,paste("select * from MyTable;"))
odbcClose(channel)

Try connecting on the default SQL server port, which is 1433, not 5000.
And check that you can connect to the correct instance using SQL mgmt studio.

I had a similar issue, with the following error:
_mssql.MSSQLDatabaseException: (18456, b"Login failed for user
'script_svc'.DB-Lib error message 20018, severity 14:\nGeneral SQL Server
error: Check messages from the SQL Server\nDB-Lib error message 20002,
severity 9:\nAdaptive Server connection failed\n")
The user I had established was a local user on the machine.
The solution for me was putting ".\" in front of the username and it then recognized it as a local user and allowed the query to work.
Your results may vary.. but I thought I would mention it.

Have you tried using pyodbc instead?
import pyodbc
cnxn = pyodbc.connect('DRIVER={ODBC Driver 13 for SQL Server};SERVER=SERVERNAME;DATABASE=testdb;UID=me;PWD=pass')
cursor = cnxn.cursor()
cursor.execute("select user_id, user_name from users")
rows = cursor.fetchall()
for row in rows:
print row.user_id, row.user_name
Don't forget to add the ODBC driver to your Windows. Go to: Control Panel > Systems and Security > Administrative Tools > ODBC Data Sources
Either the 32-bit or 64-bit version depending on your computer.
Then you click on the System DNS file. If you do not see any MySQL driver you have to click ADD. It brings up a list, from that list select the MySQL driver.
For me, it was ODBC Driver 13 for SQL Server. Click finish. Once you do that then you have to change your connection line in your code to the corresponding Driver that you just filled out.
Source: pyodbc + MySQL + Windows: Data source name not found and no default driver specified

Python scripts and MySQL

Good day!
I have a question annoying me. I setup Apache server/MySQL/PhpMyAdmin on my PC. And i'd like to write some scrips on python3 to work with database. I setup my db on localhost. But now the local network has another one computer.
I wish my friend could access the database through my ip. like (http :// 192.168.xx.xx / pma).
and now it works!
My friend loves python too. And there is a problem: When he's run script, python waits 30 sec and:
"Can't connect to MySQL server on %r (%s)" % (self.host, e))
pymysql.err.OperationalError: (2003, "Can't connect to MySQL server on '192.168.
xx.xx' ([WinError 10060] A connection attempt failed because the connected part
y did not properly respond after a period of time, or established connection fai
led because connected host has failed to respond)")
There peace of code to connect:
import pymysql
con = pymysql.connect(host='192.168.xx.xx', user='root', passwd='xxx', db='test')
cur = con.cursor()
print(con)
Help my friend to work with my database!
Thanks you!

You have to give remote access to your mysql database.
Then give grant to your user.
GRANT ALL PRIVILEGES ON *.* TO 'root'#'%' IDENTIFIED BY 'password' WITH GRANT OPTION;

Ident connection fails via psycopg2 but works via command line

When I try to connect to my postgres server via psycopg2 with a bit of code like this (running python as "username"):
psycopg2.connect(database="apis_master")
I get an error
psycopg2.OperationalError: FATAL: Ident authentication failed for user "username"
But when I run psql straight from the command line (as user "username") like so:
psql -d apis_master
I connect with no problem.
I can't see what is different between these two connection methods. Am I missing some configuration option with psycopg2?

Your command line user and your python user are different. When you instantiate psycopg2 object, pass user credentials:
db = psycopg2.connect(
host = 192.168.0.1, # example IP, use 'localhost' if local, otherwise the IP of the server where Postgre is located.
database = 'apis_master'
user = 'my_db_user',
password = 'my_db_password'
)
This should solve your connection problem.

The problem was that there were two PGSQL instances running on this system. One was 8.4 and not configured to ident with my username, the other was 9.1 and had my username. Command line psql was automatically picking 9.1 running on a non-standard port while psycopg2 was using the default port. Specifying the port in the psycopg2 connection line fixed the problem.