Trying to install floodlight controller in mininet
DNS is not configured or there is no connectivity with the Internet.
Related
I'm having problems with getting proxy setup right in a docker container. I want to download a file from github, but get unable to resolve host address error from wget. Now, how do I debug what goes wrong in accessing the host? I want to see steps like :
requesting `docker.host.internal:3128" (my local proxy)
requesting "company.com/proxy:1234"
requesting "github.com".
What command line utility can get this information? or what other approach can I use to debug inaccessible host?
I had similar issues and found it helpful to debug by comparing behavior of curl locally and via docker.
curl google.com
docker run -it curlimages/curl google.com
If docker network setup is fine, result should be the same.
"unable to resolve host address" points to a problem with DNS resolution. You can try to ping the IP address of github. If you use docker behind a proxy, you need to make some configuration (https://docs.docker.com/network/proxy/). To test connectivity you can use: ping, curl, wget.
I am trying to use Harbor as a Docker registry on Ubuntu 20. I followed the official documentation. As I wanted to connect to Harbor via HTTP, I followed the instructions there.
I am still getting this kind of error:
$ sudo docker push harbor_example:5000/ubuntu
Using default tag: latest
The push refers to repository [harbor_example:5000/ubuntu]
Get http://harbor_example:5000/v2/: dial tcp :5000: connect: connection refused
Did I miss something in the setup of Harbor and/or Docker?
Best regards
It turns out it works when you specifically add the port 80 in /etc/docker/daemon.json
{
"insecure-registries" : ["harbor_example:80", "0.0.0.0"]
}
After I install docker.io to my computer(Ubuntu 16.04), the hosts machine internet goes away.
Could anyone help me, how can I use both internet and the installed docker.
I could write this here, because I removed docker, and now it is not on my machine.
Thanks in advance!
I had to add the following lines into /etc/docker/daemon.json:
{
"bip": "172.26.0.1/16"
}
If you are using VM environments, have you a) set the VM network adapter to dhcp and b) shared your main connection to the VM network adapter?
I tried to push signed images from a machine (A) to a registry on another machine (B).
docker tag busybox:latest ubuntu:5005/busybox:latest
docker push ubuntu:5005/busybox:latest
The push refers to a repository [ubuntu:5005/busybox] .... Error: Status 404 trying to push repository busybox ... .
telnet ubuntu 5005
Trying 127.0.1.1...
telnet: Unable to connect to remote host: Connection refused
Are there any extra settings in order to push signed images on a diff machine. Or just to push without signing? Thanks a lot!
If you can't reach this, make sure your ports are properly exposed on the machine and that your networking resolves "ubuntu" to your newest machine correctly.
It's probable Machine A has no rule allowing ubuntu to resolve to <machine B>.
Make sure you docker login as well once you verify this, too.
This docs helped me to solve the problem.
https://docs.docker.com/registry/insecure/.
https://docs.docker.com/registry/deploying/#get-a-certificate.
https://www.digitalocean.com/community/tutorials/how-to-set-up-a-private-docker-registry-on-ubuntu-14-04.
I am trying to install Hadoop on Docker on top of docker-machine. Long story short, I need to be able to curl 172.17.0.1:8500.
That works just fine from within the Virtual Machine but fails from within MacOS.
curl: (7) Failed connect to 172.17.0.1:8500; Operation timed out
What should I do to go around this issue?
Krisztian Horvath from sequenceiq/docker-ambari was kind enough to help me out with that.
So, what you need to do is to
docker-machine ip default
to get VM_IP your virtual machine IP and then
sudo route add -net 172.17.0.0/16 VM_IP