My postgres DB is in AWS instance running windows server 2012.
My tableau desktop is in local machine.
While connecting to the DB using external instance IP and default postgres PORT 5432 , it shows the error
Unable to connect to the ODBC Data Source.
Check that the necessary drivers are installed and that the connection properties are valid.
Unable to connect to the server "ec2-xx.xx.xx.xx.ap-south-1.compute.amazonaws.com".
Check that the server is running and that you have access privileges to the requested database.
I have made sure that:
AWS security group is configured for all incoming ports
Windows server 2012 firewall is accepting all inbound traffic.
My local desktop is allowing to send traffic to remote server.And I can telnet hostIP/hostname PORT successfully.
Postgres service is running on 5432 port.
Going by the points you mentioned, I would suggest to see if you have the required drivers installed for postgres. Also, if possible for you for the time being you can install any client temporarily like sqldeveloper(later you can remove this) on the tableau desktop.
Now because you are able to telnet Ip 5432, you can test your connection from the client, If this doesnt work u know that the problem is in configuration else we need to dig more into that.
It seems like I have not set the pg_hba.conf file correctly for postgres. Allowing the connection request from all external IPs let me resolve the issue.
Adding the line at the end of the file,
host all postgres 0.0.0.0 md5
Related
I am trying to explore a way to connect postgres 13 cloud sql instance with only private IP from my local windows machine ..
I am able to connect through a compute instance tied with the same subnet as a default GCP behavior..
I want it to be secure my cloud instance to be accessible only through a VPN setup.. I have a Open VPN CE installed and whitelisted the Open VPN ip in the GCP firewall rule. Still getting the error message.
psql: error: could not connect to server: Connection timed out
Is the server running on host "{ip_address}" and accepting
TCP/IP connections on port 5432?
There are methods though to connect via private IP having enabled cloud proxy. But is there a way that i can make it happen via other VPNs.?
When you receive this error most of the time it is due to not having
PostgreSQL configured to allow TCP/IP connections or at least no
connections from your particular workstation. Here is a list of
common causes to this problem:
a) postgresql.conf is not set up to allow TCP/IP connections.
You'll want to look at the listen_address configuration parameter.
b) postgresql.conf is not set up to allow connections on a
non-standard port number. To determine this look at the port
configuration option.
c) Authentication rules in PostgreSQL's access configuration file
(pg_hba.conf) are not set up to allow either your user or IP
address to connect to that database. See the
official-documentation for more information on setting up your
pg_hba.conf properly.
d) Ensure that there are no firewalls, such as iptables that are
keeping your local system from even establishing a connection to the
remote host. For common PostgreSQL problems and possible solutions,
check here.
You have to edit the postgresql.conf file and change the line
with 'listen_addresses'. This file you can find in the
/etc/postgresql/13/main directory. To connect PostgreSQL server from other computers, you have change this config line in this way:
listen_addresses = '*'
Then you have to edit the pg_hba.conf file, too. In this file you
have set, from which computers you can connect to this server and
what method of authentication you can use. Usually you will need
similar line:
host all all <IP address> md5
For detailed steps, you can check here.
Finally i had to set the cloud SQL proxy on a f1-micro VM instance having only private IP ..
Whitelisted the port 5432 on the firewall rule.
From table plus i use the private IP of the vm instance to connect to my cloud postgress instance.
Very well If somebody has other alternatives please do let me know.
I successfully created a Compute Engine VM instance, and installed MySQL on it using this guide:
https://cloud.google.com/solutions/setup-mysql
Now I want to connect to it from App Engine and from my home too if possible.
Using this guide: https://cloud.google.com/appengine/docs/standard/python/connecting-vpc
I created the connector, giving it the suggested 10.x.x.x/28 IP address.
In my app engine's app.yaml I inserted:
vpc_access_connector:
name: projects/xxxxxxxxxx/locations/europe-west3/conectors/xxxxxx
The VM instance shows an internal IP of 10.x.x.x and an external IP of 34.x.x.x
I am trying to connect from PHP using this line:
new mysqli($servername, $username, $password, $dbname, 3306, null);
but I get different errors.
When connecting to 34.x.x.x from my home:
mysqli::__construct(): (HY000/2002): No connection could be made because the target machine actively refused it.
(I even created a Firewall rule to allow all traffic from my home IP)
When connecting to10.x.x.x from app engine:
2002: Connection timed out
When connecting to 10.x.x.x from app engine:
2002: Connection refused
How can I make a connection?
My first guess is that the service inside the instance is not up and running, check if the service of MySQL is running and listening, you can try this by doing a nmap test vs. the public IP of your MySQL VM instance nmap 34.0.0.0. You should see something like this (if you are using the standard port):
PORT STATE SERVICE
22/tcp open ssh
80/tcp closed http
443/tcp closed https
3306/tcp open mysql
Remember that there are two firewalls you need to take care of on GCP, (VPC firewall & OS firewall). So if you are not able to see this port start the SQL service by connecting into your VM instance and typing sudo systemctl start mysql, now run again nmap 34.0.0.0 and you should see the service.
To connect from App Engine to MySQL on Compute Engine VM instance just follow this other guide .
To connect from your home It will be better for you to connect to the instance via SSH and then to access your database, or you can keep connecting by a VPN to access it with the internal IP address if you need to connect directly to the socket, just take care to avoid hitting the limitations or missing something like IAM roles and permission needed for this connection.
I have a compiled Go project that I want to deploy to an AWS EC2 instance. I just simply upload the application and run ./application on the remote server.
In the terminal, the application is running and says he's listening to localhost:3000.
I've already added the 3000 port to the security group.
However, when I tried to access it in my browser using <public-ip>:3000, it always shows connection refused, whether I've run the application or not.
I tried to run the app locally, it does work.
So is it because I deploy it incorrectly?
It is a bit difficult to help you because of no code being shared.
Some reasons why you got connection refused:
Your application is listening only localhost:3000
EC2 security group does not expose port 3000
How to fix:
Most applications are defining the host address on a config file or env variables. If you have access to change it, change it from localhost:3000 to 0.0.0.0:3000 to accepts connection from all IP or to your_ec2_public_ip:3000
If host address is hardcoded and you have access to code, change the code per above
If you don't have access to config or code to change the host address, then add a reverse proxy to route the incoming call to localhost:3000. This is a good link about using Nginx as reverse proxy https://docs.nginx.com/nginx/admin-guide/web-server/reverse-proxy/
Ensure EC2 Security Group allowing inbound connection for the designated port, in this case, is 3000 if you manage to route the incoming to your_ip:3000
I have set up a a micro EC2 instance on AWS. Currently, I am using the free tier in Oregon. There are two problems which I am facing.
When I try to SSH the instance using the public DNS, it says host does not exist but when I try conencting it using the public IP, it connects to it. What setting is needed to use the public DNS ?
I have opened the SSH client using the IP address. I want to set up my application which needs Node.js and MongoDB. I installed Node.js using this
Next I installed MongoDB using this
Then I connected to my instance using Filezilla and uploaded my code to it. I then start my node application which uses socket.io.
When I try to connect to socket.io server using web browser, I get a message which says connection refused "error 111". I have opened TCP port 80 in instance's security groups. In iptables, I have forwarded port 80 to 8080, but still it does not work. I have also checked that the firewall is disabled in ec2. Kindly help me to resolve this issue.
Did you check if all of the necessary ports are open on Amazon Security Policy?
What you can do is to allow all traffic on Amazon Security Policy for test and see if the connection goes well or not.
You might also check if you need access DB from outside. In that case, you also have to open the mongodb port and setup mongodb correctly as well.
Other tools that might useful to test firewall and connection issue will be tcpdump and syslog file
For the dns issue, did you try to nslookup on that name and see if the IP shown matches your server IP?
As Amazon gives a long DNS hostname for the server, I always use my own domain name. It's much easier.
example : ec2.domainname.com, which points to the Amazon IP address
Hope that help.
My problem is resolved now..
For the DNS issue, earlier I needed proxy to access internet, so I guess the DNS name was not getting resolved. When I tried using proxy free internet, I was able to ssh using public DNS.
And regarding connection to socket.io, I used port 8080 instead of 80 and used "sudo node main.js" to run my node file. Now I am able to connect to the socket.io server and MongoDB.
Another thing which I want to ask is that would running the node file with sudo rights create some security issue ?
Thanks for the answer! That also worked for me. I had the same problem trying to connect through sockets (http://myipaddress:3000) to a node.js server, i tried opening ports on the actual ec2 instance and disabling the firewall through SSH but nothing worked. Had to go to Security Groups on the ec2 console and open a new inbound tcp rule enabling that port
I had to stop then start my ec2 database server running postgresql. Now after it is started, i get the following error message from my django web server
could not connect to server: Connection refused Is the server
running on host "54.235.119.193" and accepting TCP/IP connections on
port 5432?
However because I use elastic IPs and reassigned the same IP (54.235.119.193) I don't think that is the issue. I also am using the same security groups as before, which allow 5432.
I think the only thing that changes when you start/stop is the internal IP but I don't remember using that anywhere in configuration
Any Ideas?
Are you using iptables or selinux? These usually get in the way on restart if not configured properly.