I have set up a container running Apache in Docker.
I understand that Apache generally runs in a multi-process manner. I am wondering, is Apache in Docker running multi-processes for the CPU of the OS running Docker?
We can see that when we run Docker on Ubuntu it is running as a single process with the ps aux command. But is it possible to be multi-process in it? This is also a question about the behaviour of Docker itself.
Related
I am fairly new and want to learn Docker and Containers, specifically web app architecture. My question is what path should I go to, if I just install Docker Desktop on Windows or just install a VM and run an ubuntu then the docker?
Thanks...
We have been using windows containers as test rigs for while now with great success. However since the last windows update, the container seems it crashes the host system (Windows Server 2019 std).
The server will be running fine for hours, then minutes after executing one of these commands it will crash.
docker run -it --rm -p 8000:80 --name core_sample mcr.microsoft.com/dotnet/core/samples:aspnetapp
docker run --name test mcr.microsoft.com/windows/nanoserver:1809
Just wondering if anybody else is experiencing the same? We already tried to reinstall the host but no joy.
Going on #cael-ras idea of trying a Ubuntu container, I installed HyverV and is now running my containers in Hyper-V isolation mode (--isolation=hyperv) instead of process mode. That seems to have fixed the issue. Thanks
https://learn.microsoft.com/en-us/virtualization/windowscontainers/manage-containers/hyperv-container
I'd like to know what processes run in VM with Docker Daemon on a Windows 10 host.
How could I connect to the VM and list those processes?
I'm guessing you mean to a remote Docker Daemon? You can use Docker Contexts to be able to run all of the standard Docker commands remotely.
Once you have a context setup for the VM Docker Daemon, you can do for example:
docker ps, docker top and so on, like this:
docker --context <VM's context name> top
If you just mean connect to the daemon locally, you can SSH into the daemon, and run the usual Linux commands.
What is the difference between starting the docker daemon using dockerd and systemctl start docker.
When would you use one over the other?
A list that is probably not comprehensive:
You can configure systemd to run docker when your system boots (systemctl enable docker).
If you start the service using systemd, you can ask systemd whether or not it's running (systemctl status docker), and the answer is authoritative (compared to running something like ps | grep dockerd, which can return false positives).
If you start the service using systemd, systemd can automatically restart it if it fails.
When running the service under systemd, output to stdout/stderr is gathered in the system journal so you can find it via journalctl -u docker.
The systemd unit may apply resource limits that improve the behavior of dockerd (e.g., removing the limits on number of files, number of processes, etc)
I use vagrant to manage VirtualBox and I want to build a cluster using Docker Swarm.
When I run the command docker node ls it shows the same hostname. Also if I run the service, they are run and shutdown immediately and run and shutdown.
Here is the vagrant file.
Here is the docker swarm result show.
I suggest installing docker-machine and then use the following script to install a swarm
Troubles using docker-machine to setup Swarm
Under the hood it still uses Virtualbox, just a more docker friendly way compared to vagrant.
Might be caused by this issue of changing the hostname before or after docker-engine:
https://github.com/docker/docker/issues/27173
After I rebooted my VM, the HOSTNAME column was correct.