I am trying to connect to a free tier redshift cluster through a python script on a local machine, and keep getting the following error:
> psycopg2.OperationalError: connection to server at "<clusterendpoint>" (<clusterip>), port 5439 failed: Connection timed out (0x0000274C/10060)
Is the server running on that host and accepting TCP/IP connections?
I am using psycopg2 using the following code:
rs_conn = psycopg2.connect(
dbname= dbname,
user= username,
password= password,
host = endpointurl,
port = port)
My VPC is publicly available. I have tried adding my ip to the security group, and have also tried adding 0.0.0.0/0 to the security group, but haven't had any luck.
I used boto3 describeclusters() to investigate the problem further, and I did notice that neither the public nor private ip matched the ip shown in the error above associated with the endpoint url. Is that normal? I know that the endpoint url is correct.
Is there a better way to investigate this issue that will give me a better idea as to where the connection is going wrong?
I am trying to build a tunnel to then connect to an Oracle DB, but tunnel cannot be opened. Error is the following:
ERROR | Problem setting SSH Forwarder up: Couldn't open tunnel localhost:1521 <> XXXXXXXXX:1521 might be in use or destination not reachable.
sshtunnel.HandlerSSHTunnelForwarderError: An error occurred while opening tunnels.
My code is set as:
self.tunnel = sshtunnel.SSHTunnelForwarder((conn_data['gateway'], int(conn_data['gateway_port'])),
ssh_username=conn_data['username'],
ssh_password=password,
remote_bind_address=(conn_data['remote_bind'],
int(conn_data['remote_port'])),
local_bind_address=(conn_data['local_bind'],
int(conn_data['local_port'])))
The code works fine if I am inside the network of the company I work for. But if I am connected through VPN, I get the above error. My guess is that the VPN is built over the same tunnel.
I tried changing the local_port and removing the local bind, but if I do that, I get the error:
cx_Oracle.DatabaseError: ORA-12541: TNS:no listener
So, how can I dynamically set the port of SSHTunnelForwarder so it can access my DB through my already set VPN?
Note: changing the VPN's configuration or not using it is not an option.
Problem solved. The issue was that my VPN was using the same port as me (which caused the first error), and my Oracle connection was pointing to this port also (what caused error ORA-12541).
To solve it, I had to change conn_data['local_port'] to another port and set the port of my oracle connection to this same port:
self.tunnel = sshtunnel.SSHTunnelForwarder((conn_data['gateway'],
int(conn_data['gateway_port'])),
ssh_username=conn_data['username'],
ssh_password=password,
remote_bind_address=(conn_data['remote_bind'], int(conn_data['remote_port'])),
local_bind_address=(conn_data['local_bind'], 1234))
self.connection.connect(conn_data['host'],
port=1234,
username=conn_data['username'],
password=password,
look_for_keys=False)
I had been working with pyodbcfor database connection in windows envirnment and it is working fine but now I want to switch to pymssql so that it is easier to be deployed to Linux machine as well. But I am getting this error:
(20009, b'DB-Lib error message 20009, severity 9:\nUnable to connect: Adaptive Server is unavailable or does not exist (localhost:1433)\nNet-Lib error during Unknown error (10060)\n')
My connection code for using both pyodbc and pymssql is:
import pyodbc
import pymssql
def connectODSDB_1():
conn_str = (
r"Driver={SQL Server};"
r"Server=(local);"
r"Database=populatedSandbox;"
r"Trusted_Connection=yes;"
)
return pyodbc.connect(conn_str)
def connectODSDB_2():
server = '(local)'
database = 'populatedSandbox'
conn = pymssql.connect(server=server, database=database)
return conn
What could be the problem? And solution?
Well after browsing internet for a while, it seems pymssql needs TCP/IP be enabled for communication.
Open Sql Server Configuration Manager
Expand SQL Server Network Configuration
Click on Protocols for instance_name
Enable TCP/IP
I have faced the same issue while using RDS(AWS database instance). We should configured the inbound outbound rules.
Do following steps to configure.
Services->RDS->DB Instances -> Select DB-> Connectivity&Security
Under Security Section
VPC security groups -> click on security group
Change the inbound rules.
Check the source IP and change into anywhere or specific IP
I am trying to make software that works on a large number of people's computers by connecting to a login server. I have set up a MSQL server using 24hosting and added a database. I then tried to access the database using python, but it gives me the error "No connection could be made because the target machine actively refused it".
I need everyone who downloads this program to be able to connect, not just this computer.
This is probably something to do with my server, and not to do with code, but I will post the code below anyway.
from os import getenv
import pymysql
server = getenv("31.220.17.13")
user = getenv("shutdow1_user")
password = getenv("DSAEWQ321")
conn = pymysql.connect(server, user , password, "tempdp")
cur = conn.cursor()
cur.execute("SELECT Host,User FROM user")
cur.close()
conn.close()
Try to run tcpdump or tshark host 31.220.17.13 to see what exactly happens.
Most likely TCP connection to mysql port is filtered (you would see RST replies on SYN send), or if you see that connection is closed by remote party after TCP session is established - that would be a sign of remote mysql server not configured properly to accept client connection for your IP/username/password/database.
I'm having an issue connecting to my local MySQL database using Python's MySQLdb library. The script has been working well previously, but I will occasionally get the MySQL error in the title. There seems to be no explanation for when the error occurs, and the script is always run from the same machine with the same arguments.
The MySQL server is running as a service on Windows XP SP3 using port 3306 (locally hosted phpMyAdmin works), and the script is run from an Ubuntu 10.04 guest operating system in Oracle VM VirtualBox.
I am currently working around this issue by opening a command prompt and executing 'net stop MySQL' then 'net start MySQL'. This allows me to run the script a few times again before resulting in the error, which I've been fixing by restarting the MySQL service.
As I am still making changes to the script, there are occasions when the script raises an exception and doesn't exit gracefully, though I do catch the exception and close the cursor and connection.
The code to connect to the database:
def __init__(self):
try:
print "Connecting to the MySQL database..."
self.conn = MySQLdb.connect( host = "192.168.56.1",
user = "guestos",
passwd = "guestpw",
db = "testdb")
self.cursor = self.conn.cursor(MySQLdb.cursors.DictCursor)
print "MySQL Connection OK"
except MySQLdb.Error, e:
print "MySQLdb error %d: %s" % (e.args[0],e.args[1])
raise
The full error generated when this happens is as follows:
MySQLdb error 2013: Lost connection to MySQL server at 'reading initial communication packet', system error: 0
Traceback (most recent call last):
File "search.py", line 45, in <module>
dataHandler = DataHandler()
File "/home/guestos_user/workspace/Search/src/data_handler.py", line 25, in __init__
db = "testdb")
File "/usr/lib/pymodules/python2.6/MySQLdb/__init__.py", line 81, in Connect
return Connection(*args, **kwargs)
File "/usr/lib/pymodules/python2.6/MySQLdb/connections.py", line 170, in __init__
super(Connection, self).__init__(*args, **kwargs2)
_mysql_exceptions.OperationalError: (2013, "Lost connection to MySQL server at 'reading initial communication packet', system error: 0")
sudo vi /etc/mysql/my.cnf
delete
bind-address = 127.0.0.1
then
sudo reboot now
That's it. Be aware that this will make your mysql server less secure as you are exposing it.
I have seen this happen when child processes try to share the same mysql connection id (solution = create new connections for each child process). I'm not sure if this is also possible when sharing connection objects with multiple threads.
However, that's only one of the many possible causes. See VVS's answer in MySQL Error 2013 for a list of troubleshooting resources.
Do you have in your MySQL server an acount called guestos#YOURIPADDRESS?
You must have an account to access to your MySQL server from YOURIPADDRESS!
For example:
Your IP address is 192.168.56.2; then you must create and account if not exist to access.
mysql> create user guestos#192.168.56.2 identified by 'guestpw';
The problem fixed for me just by restarting my mac. Though there might be a more specific fix for it.
I received a similar error when attempting to connect to my MySQL server remotely through a user with the sufficient permissions.
After editing the /etc/mysql/my.cnf file to include
[mysqld]
bind-address=xx.xx.xxx.xxx
where xx.xx.xxx.xxx is my local IP address, I began experiencing the exact same error as you. From there, I found an answer regarding this issue (answered by Coffee Converter) which worked for me, and can be found here: Lost connection to MySQL server at 'reading initial communication packet', system error: 0 on a windows machine
All I did to fix the issue for myself was edit the /etc/hosts.allow to include
mysqld: ALL: allow
Works great now! I hope this helped :)
Could you change the bind-address=localhost and restart MySQL server? Seems like this issue is related to yours: http://forums.mysql.com/read.php?152,355740,355742#msg-355742
Also this-
If MySQL port is wrong result is MySQL client error 2013 "Lost
connection ...". Note that this error also occurs if port forwarding
is disabled in SSH configuration (the configuration parameter
'AllowTcpForwarding' is set to 'no' in the 'sshd_config' file). It
(here) simply tells that there is no connection from SSH to MySQL for
some reason. But the mySQL client API 'thinks' there was one
connection and that is why is says 'Lost connection ...' and not
'Can’t connect...'. There was one successful connection - but not to
the MySQL server - to the SSH daemon only! But the MySQL client API is
not designed to 'see' the difference!
Refer this.
I run a windows server and from time to time the php-win.exe will load and stay in the processes list on the windows task manager.
If you know the host file is correct, then kill the php-win.exe process and restart iis iisreset
If you are running windows then your problem should be solved.
I've had the exact same mysql error (ERROR 2013 (HY000): Lost connection to MySQL server at 'reading initial communication packet', system error: 0=) and have resolved it by adding a newline to /etc/hosts.deny.
Possibility: your database is corrupted.
I encountered this situation when I was running an UPDATE statement on a specific row of a specific table. (Specifically, I was editing an item in a Django Admin site.) Most of the time the database worked just fine.
I finally resolved the problem by running:
OPTIMIZE TABLE `your_table`
After that everything was OK, no connection lost.
Conclusion:
The problem "Lost connection to MySQL server at 'reading initial communication packet'", sometimes "Can't connect to MySQL server on '127.0.0.1'", could possibly be resolved by running a full database optimization if the database is corrupted. For more info, read this.
Just to further extend the list of possible causes: it could also be as banal as wrong connection data/credentials. I encountered this error in conjunction with sqlalchemy:
sqlalchemy.exc.OperationalError: (mysql.connector.errors.OperationalError) 2013 (HY000): Lost connection to MySQL server at 'reading initial communication packet', system error: 0
In my code I connect to several different databases and once in a while it happens that I don't get the mapping between the db connections and their credentials (e.g. ip address of server, db-name, password etc.) right, which then also results in the 2013-error (in this case wrapped into an sqlalchemy operational error).
setting.py file set like:
'ENGINE': 'django.db.backends.mysql',
'NAME': 'test2',
'USER': 'root',
'PASSWORD': '',
'HOST': 'localhost',
'PORT': '3308',
This bug report might be of interest to you. Don't know if this will help you, but some were able to solve it by using the name of the server rather than the ip address in the connection properties.