Private IP on Azure MySQL Flexible Server - azure-mysql-database

When creating MySQL Flexible Server (DBaaS) on Azure that is not publicly accessible a private DNS zone is being created making that MySQL Flexible Server accessible via a hostname. While debugging why I'm able to connect to MySQL Flexible Server from a jumpbox VM, but not when using Virtual Network Gateway - Point to site connection - OpenVPN, I've discovered that the DNS zone has a private IP:
I'm able to connect to MySQL Server using this IP from both jumpbox VM and from local computer using point-to-site OpenVPN.
What is that IP? Since connecting to MySQL via IP is easier than setting up Private DNS zone and connecting via hostname, why this IP is not documented? Can we use it in production?

Wondering if you have custom DNS forwarder setup as shared below
https://learn.microsoft.com/azure/mysql/flexible-server/concepts-networking-vnet#connecting-from-on-premises-to-flexible-server-in-virtual-network-using-expressroute-or-vpn

Related

How do I configure my Aurora SQL database to be accessible using pgAdmin and fix a timeout expired error?

Following this tutorial, I set up an Aurora PostgreSQL database. I then tried to access the database from my computer using pgAdmin. However, pgAdmin gives the error: "Unable to connect to server: timeout expired"
I have tried the following things:
Ensured that the database is set to be publicly accessible
Verified that the database has an IP address (I ran nslookup on my local machine, and it returned a public IP address).
Verified that the database is in a public subnet (it is launched in two subnets, one of which is a public subnet with an Elastic IP address and one of which is a private subnet which directs traffic to a NAT gateway)
Ensured that my database is configured to use port 5432
Modified the security group to add inbound rules allowing TCP traffic on port 5432 from any IPv4 or IPv6 address
Ensured that I can send outbound traffic on port 5432 from my computer using this site
It looks like you have deployed the Aurora DB cluster into two subnets of a VPC and the problem is that one subnet is public, while the other is private. I suspect the DB will be accessible publicly as long as the public DNS resolves to the DB instance in the public subnet, but will be unreachable when it resolves to the instance in the private subnet (though I have not verified this).
To correct this and make the cluster publicly accessible, deploy the DB into public subnets only.

AWS Lambda default VPC - unable to connect with mongodb running on EC2

Can anyone help me to figure out database connection issue from Lambda to MognoDB (running on EC2, ubuntu machine)
I have following scenario -
Installed and running MongoDB on EC2 (it is in default VPC)
Enable port 27017 for private IP of API EC2
Enable port 27017 for SECURITY_GROUP, like this -
Deployed Lambda function within default VPC and the same security group as assigned to MongoDB EC2 server.
With above situation my Lamda function is not able to connect with MongoDB EC2 server, however if I open the PORT 27017 globally, then it is working fine.
Can anyone help please?
Given that the Lambda function and MongoDB instance have the same security group, you should:
ensure that the security group allows traffic inbound from itself
your DB client connects to the private IP of the DB server (or resolves its DNS name using the VPC DNS resolver, which will yield the private IP) rather than its public IP

Why can't App Engine connect to Compute Engine VM instance?

I have a VM instance (e2-micro) on GCP running with postgres. I added my own external ip address to pg_hba.conf so I can connect to the database on my local machine. Next to that I have a nodeJS application which I want to connect to that database. Locally that works, the application can connect to the database on the VM instance. But when I deploy the app to GCP I get a 500 Server Error when I try to visit the page in the browser.
These are the things I already did/tried:
Created a Firewall rule to allow connections on my own external ip address
Created a VPC connector and added that connector to my app.yaml
Made sure everything is in the same project and region (europe-west1)
If I allow all ip addresses on my VM instance with 0.0.0.0/0 then App Engine can connect, so my guess is that I'm doing something wrong the connector? I use 10.8.0.0/28 as ip range while the internal ip address of the VM instance is 10.132.0.2, is that an issue? I tried an ip range with 10.0.0.0 but that also didn't work.
First check if your app uses a /28 IP address range (see the documentation):
When you create a connector, you also assign it an IP range. Traffic
sent through the connector into your VPC network will originate from
an address in this range. The IP range must be a CIDR /28 range that
is not already reserved in your VPC network.
When you create a VPC connector a proper firewall rulle is also created to allow traffic:
An implicit firewall rule with priority 1000 is created on your VPC
network to allow ingress from the connector's IP range to all
destinations in the network.
As you wrote yourself when you create a rule that allows traffic from any IP it works (your app can connect). So - look for the rule that allows traffic from the IP range that your app is in - if it's not there create it.
Or - you can connect your app to your DB over public IP's - in such case you also have to create a proper rule that will allow the traffic from the app to DB.
Second - check the IP of the DB that app uses.
My guess is that you didn't change the IP of the DB (that app uses) and it tries to connect not via VPC connector but via external IP and that's why it cannot (and works only when you create a firewall rule).
This answer pointed me in the right direction: https://stackoverflow.com/a/64161504/3323605.
I needed to deploy my app with
gcloud beta app deploy
since the VPC connector method was on beta. Also, I tried to connect to the external IP in my app.yaml but that needed to be the internal IP ofcourse.

Connecting Google Cloud Platform's compute engine and app engine via VPC connector

I'd like to know in detail how to connect google compute engine virtual machine instance and app engine.
I've set up a virtual machine instance on Google compute engine, and my Postgres server is running there, following this tutorial: https://cloud.google.com/community/tutorials/setting-up-postgres
I've deployed my flask app under the same project on Google Cloud Platform, creating an app engine instance.
I searched on how to connect compute engine and app engine together, and it seems it should be possible through a VPC connector: connect Google App Engine and Google Compute Engine
This is what my VPC connector looks like:
Serverless VPC access
Name Network Region IP address range Min. throughput Max. throughput
connector-name default europe-west2 10.8.0.0/28 200 300
On my compute engine, I have my VM instance like so:
Name Zone Internal IP External IP
some-name europe-west2-c 10.154.0.2 (nic0) 34.89.113.193
On my flask app, I'm trying to connect to my remote DB like so:
db = PostgresqlExtDatabase(
"some-name", # databse name
user="postgres",
password="some-password",
host="10.154.0.2", # remote host internal ip
port=5432,
)
db.connect()
This is my app.yaml for the vpc access part, I've followed this reference: https://cloud.google.com/appengine/docs/standard/python/connecting-vpc#configuring
vpc_access_connector:
name: projects/some-name/locations/europe-west2/connectors/connector-name
If I understood correctly, if the VPC connector is present, I should just be able to connect using the internal IP address of my VM instance(this case, 10.154.0.2)?
The problem is, when the app is deployed for production, It is still complaining that it cannot connect:
2020-09-26 12:54:51 default[20200926t134815] Is the server running on host "10.154.0.2" and accepting
2020-09-26 12:54:51 default[20200926t134815] TCP/IP connections on port 5432?
If it's connected internally I assume I don't have to add that internal IP to firewall rules, although I did try that as well. As for firewall rules, I have allowed my local machine's IP address so I can connect to the remote Postgres server via PgAdmin.
I've actually tried External IP(34.89.113.193) as well although that doesn't make sense to me.
I'm a bit of a noob on networks and backend stuff in general, any help would be much appreciated.
UPDATED 1
This is my firewall rules:
Direction
Ingress, Egress
Action on match
Allow
Source filters
IP ranges
92.40.176.9/32
78.146.103.141/32
10.154.0.2
Protocols and ports
tcp:5432
Image for reference: Screenshot for the list of firewall rules
It turns out the firewall / postgres configurations were all ok, but because this VPC connector method was on beta, I needed to run:
gcloud beta app deploy
instead of the usual
gcloud app deploy.
This command then updated gcloud Beta Commands and prompted me to enable API:
API [appengine.googleapis.com] not enabled on project [742932836941]. Would you like to enable and retry (this will take a few minutes)? (y/N)?
After enabling this everything worked fine.
Per the information provided seems like both VPC firewall rules and the connector are well configured.
However, based on the messages
2020-09-26 12:54:51 default[20200926t134815] Is the server running on host "10.154.0.2" and accepting
2020-09-26 12:54:51 default[20200926t134815] TCP/IP connections on port 5432?
Seems like the VM or server using 10.154.0.2 is not accepting requests on port 5432 or the port has not been opened, you can use this site to do a port scan.
Based on the guide you followed to create PostgreSQL you are using Ubuntu as OS, therefore I suggest you open the port in ubuntu and see if the issue persists.

Unable to connect to CloudSQL instance that is part of a VPC network

I have created a CloudSQL instance which was part of a VPC I have created.
I'm able to connect to this CloudSQL using CloudSQL Proxy service. But I'm unable to connect to this instance using public IP of the instance though I added the firewall rule to this VPC.
The error I'm getting:
Unable to connect to host <public-ip-of-cloudsql>, or the request timed out.
Be sure that the address is correct and that you have the necessary privileges, or try increasing the connection timeout (currently 10 seconds).
MySQL said:
Can't connect to MySQL server on '<public-ip-of-cloudsql>' (4)
Following is the firewall rule I added and provided my home IP address in the blocked out area.
Please let me know if I'm missing something. I can provide more details if needed.
These are the steps you should follow in order to connect to Cloud SQL using the public IP:
Created a Cloud SQL instance, including configuring the default user.
Assuming you use a local client:
2.Install the client.
3.Configure access to your Cloud SQL instance.
4.Connect to your Cloud SQL instance.
You can find a detailed explanation here: Connecting MySQL client using public IP
If you are using the Cloud SQL proxy to connect via public ip, it requires port 3307 to be open to the address.
If you aren't using the Cloud SQL proxy to connect via public ip, you need to authorize your external IP.
I was able to connect CloudSQL which is part of a VPC by just adding the client IP address as Authorized networks.
It's weird, I tried many times before but couldn't succeed. It is working now.
Thanks, guys for answers.