In general docker is used, it has two containers: nginx and a container for django.
Postgresql is on the host separately, not in the docker container.
I tried to do something like this in postgresql config:
host all all 0.0.0.0/0 md5
So, we allow anyone to connect to anyone, because as I understand the address of the container is changing, but I think this is not very safe.
Tried in docker-compose specify containers network_mode: "host" and change a little config nginx, yes in this case works, but I do not like the idea that all addresses will be "merged" with the host.
Also tried this:
extra_hosts:
- "host.docker.internal:host-gateway"
And also doesn't work.
In all cases I got error:
could not connect to server: Connection refused
Is the server running on host "172.17.0.1" and accepting
TCP/IP connections on port 5432?
Is there any other way to connect to postgresql from the container?
OS: Ubuntu 22.04
Back: Django
Config docker-compose
Dockerfile config
Related
I have a machine X with a lot of IPs, podman-compose with OpenSearch and OpenSearch Dashboards links the images to the wrong (unexposed) IP. I tried to force the IP but if I do so, podman-compose would break. How can I do so?
I tried to add an IPv4 in the docker-compose.yml, I tried to modify the images and force the right IP whenever I found 0.0.0.0, but it keeps breaking.
Docker / Podman container IPs are not accessible from external clients.
You need to expose TCP or UDP ports from your container to the host system and then clients will connect to :.
The host port and the container port do not need to be the same port.
i.e. you can run multiple web server containers all using port 80 however you will need to pick unique ports on your host OS that are not used by other services to port-map to the containers. i.e 80->80, 81->80, 8080->80 etc.
Once you create the port definitions in your container configuration Podman will handle the port forwarding from the host to the container.
You might need to open the ports on the host firewall to allow clients to connect. 0.0.0.0 is another way of representing the local host.
Let say your host is 10.1.1.20 and your OpenSearch Dashboards container is 172.16.8.4 and your dashboard web app is configured to listen on port 5001/TCP.
You will need a ports directive in your docker-compose.yml file to map the host port 5001 to the container port 5001 similar to the below.
containers:
opensearch-dashboard:
ports:
- "5001:5001"
As long as port 5001 is permitted on your host firewall, the client should be able to connect using https://10.1.1.20:5001/
I am connecting to a postgresql docker service with the following commands :
docker create --name postgres-demo -e POSTGRES_PASSWORD=Welcome -p 5432:5432 postgres:11.5-alpine
docker start postgres-demo
docker exec -it postgres-demo psql -U postgres
I can successfully connect to postgresql conatiner service
Now I want to connect to PgAdmin4 to make some queries to the existing data in postgres database
However I keep having this error
The IP address that I am using is the one I extracted from docker inspect DOCKERID
I have restarted the postgresql service on windows but nothing happens. What I am doing wrong ?
Thanks
In fact, what you get with docker inspect(172.17.0.2) is just the ip of container, to visit the service in container, you need port binding host's port to container's port.
I see you already used -p 5432:5432 to do it, so please get the ip of host using ip a s, then if you get e.g. 10.10.0.186, then use this host ip to visit the service, use 5432 as a port.
To publish a port for our container, we’ll use the --publish flag (-p for short) on the docker run command. The format of the --publish command is [host port]:[container port]. So if we wanted to expose port 8000 inside the container to port 3000 outside the container, we would pass 3000:8000 to the --publish flag.
A diagram let you know the topologic of docker network, FYI:
You should try to connect to:
host: 0.0.0.0
port: 5432
while your docker container is up and running.
I just installed Kubernetes with minkube on my desktop(running Ubuntu 18.10) and was then trying to install Postgresql on the desktop machine using Helm.
After installing helm, I did:
helm install stable/postgresql
When this completed successfully, I forwarded postgres port with:
kubectl port-forward --namespace default svc/wise-beetle-postgresql 5432:5432 &
and then I tested connecting to it locally from my desktop with:
psql --host 127.0.0.1 -U postgres
which succeeds.
I attempted to connect to postgres from my laptop and that fails with:
psql -h $MY_DESKTOP_LAN_IP -p 5432 -U postgres
psql: could not connect to the server: Connection refused
Is the server running on host $MY_DESKTOP_LAN_IP and accepting TCP/IP connections on port 5432?
To ensure that my desktop was indeed listening on 5432, I did:
netstat -natp | grep 5432
(Not all processes could be identified, non-owned process info
will not be shown, you would have to be root to see it all.)
tcp 0 0 127.0.0.1:5432 0.0.0.0:* LISTEN 17993/kubectl
tcp6 0 0 ::1:5432 :::* LISTEN 17993/kubectl
Any help anyone? I'm lost.
you need to configure postgresql.conf to allow external client connections look for listen parameter and set it to *, it is under your postgres data directory, and then add your laptop's ip in pg_hba.conf. It controls the client access to your postgresql server, more on this here - https://www.postgresql.org/docs/9.3/auth-pg-hba-conf.html
In my case the solution was a little bit of deeper understanding of networking.
For clarity, let's call the machine on which minikube is installed "A".
The IP of this machine as it is visible from other computers on my Wifi maybe be say: 192.100.200.300.1
Since Postgres was being exposed on port 5432, my expectation was that postgres should be visible externally on: 192.100.200.300.1:5432.
But this understanding is wrong which is what was leading to unexpected behavior.
The problem was that minikube runs in a VM and it gets its own IP address. It doesn't simply use the IP of the machine on which it is running. Minikube's IP is different from the IP
of the machine on which it is running. To find out the IP of minikube, run: minikube ip. Let's call this IP $MINIKUBE_IP.
And then I had to setup port forwarding like:
kubectl port-forward --address "192.100.200.300" --namespace default svc/wise-beetle-postgresql 5000:5432 &
So now, if you called a service on: 192.100.200.300:5000 it would be forwarded to port 5432 on the machine which is running minikube and then 5432 would be received by your postgres instance.
Hope this untangles or clarifies this problem that others might encounter.
I've create a postgresql instance into my openshift origin v3. It's running correctly, however I don't quite figure out why I am not able to reach it remotely.
I've exposed a route:
$oc get routes
postgresql postgresql-ra-sec.192.168.99.100.nip.io postgresql postgresql None
$ oc get services
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
postgresql ClusterIP 172.30.59.113 <none> 5432/TCP 57m
This is my route:
I'm trying to get access to this instance from an ubuntu os. I'm trying to get access using psql:
$ psql --host=postgresql-ra-sec.192.168.99.100.nip.io --dbname=tdevhub
psql: could not connect to server: Connection refused
Is the server running on host "postgresql-ra-sec.192.168.99.100.nip.io" (192.168.99.100) and accepting
TCP/IP connections on port 5432?
Otherwise:
$ psql --host=postgresql-ra-sec.192.168.99.100.nip.io --port=80 --dbname=tdevhub
psql: received invalid response to SSL negotiation: H
I've checked dns resolution, and it seems to work correctly:
$ nslookup postgresql-ra-sec.192.168.99.100.nip.io
Server: 127.0.0.53
Address: 127.0.0.53#53
Non-authoritative answer:
Name: postgresql-ra-sec.192.168.99.100.nip.io
Address: 192.168.99.100
EDIT
What about this?
Why is there this redirection? Could I try to change it before port-forwarding?
Exposing a service via a route means that your enabling external HTTP traffic. For a service like Postgresql, this is not going to work as per your example.
An alternative is to port forward to your local machine and connect that way. So for example, run oc get pods and then oc port-forward <postgresql-pod-name> 5432, this will allow you to create the TCP connection:
Run psql --host=localhost --dbname=tdevhub on the host machine to verify this.
There is also the option, in some instances at least to assign external IP's to allow ingress traffic. See the OpenShift docs. This will be more complicated to achieve but a permanent solution as opposed to port forwarding. It looks like you are running oc cluster up or minishift however so not sure how viable this is.
In theory while the answer of the port forwarding is correct and the only way I made it work I would say that in Openshift 3.x you could use a tcp route for this https://documentation.its.umich.edu/node/2126
However it does not seem to work (at least for me) in Openshift 4.x
Also I don't personally like the port forwarding because this assumes you have to establish a connection with a user that can connect to the cluster and has permissions with namespace to do what it needs to do.
I would much rather suggest the ingress solution
https://docs.openshift.com/container-platform/4.6/networking/configuring_ingress_cluster_traffic/configuring-externalip.html
I can't connect my Postgres container with my golang webapp container.
i got following error:
panic: dial tcp [::1]:5432: getsockopt: connection refused
My docker compose file:
http://pastebin.com/5LQfn3gy
Any idea how i can fix that?
Since the IP you specified relates to your host and not your docker environment and you're running your app inside docker too, just omit the IP:
ports:
-5432:5432
So you'd just need to pass the Postgres alias, followed by its port to your go app (either as an env var or a flag).