Mariadb10.3 was installed as Docker on Mac, and the collaction-server value in the /etc/mysql/my.cnf file was modified.
After modification, I tried to restart the container, but when I entered the'docker ps -a' command, the Status was displayed as Exited(1).
So I entered docker logs [container name] and the following error was displayed.
The setting parameter was incorrectly written as'collection-server=utf8_unicode_ci'.
So the container did not run.
I've looked at several ways, but I can't find a way to modify the internal files without running the container.
I know that you shouldn't tamper with files inside the Docker container.
My question may be,'How do I edit a file inside the computer without turning on the computer?', but I don't think that the answer is to delete the container and create a new one.
Of course, deleting the container and installing a new one will save time and may be the simplest method. But I thought in a different way.
If a company that actually operates this docker container has the same mistake as me and cannot operate the container, it must be a very fatal mistake.
Because of that, I don't know... I think there is definitely a way.
I would like advice on a solution to this method.
Related
When i want to start my DDEV Project an Container stucks at creating
Container ddev-oszimt-lf12a-v2-db Started
Error Message:
Failed waiting for web/db containers to become ready: db container failed: log=, err=health check timed out after 2m0s: labels map[com.ddev.site-name:oszimt-lf12a-v2 com.docker.compose.service:db] timed out without becoming healthy, status=
Its an Error i also had with some other projects.
In the Error Log is no information about this.
What could the Problem be and how do i fix it?
This isn't a very good place to study problems with specific projects, our Discord Channel is much better, or the DDEV issue queue.
But I'll try to give you some ideas about how to study and debug this.
Go to the Troubleshooting section of the docs. Work through it step-by-step.
As it says there, try the simplest possible project and see what the results are.
If the problem is particular to one particular project, see if you can remove customizations like .ddev/docker-compose.*.yaml files and config.*.yaml and non-standard things in the config.yaml file.
To find out what the causes the healthcheck timeout, see the docs on this exact problem, in your case the db container is timing out. So first, ddev logs -s db to see if something happened, and second docker inspect --format "{{json .State.Health }}" ddev-<projectname>-db.
For more help, you'll need to provide more information with things like your OS, Docker Provider, etc, and the easiest way to do that is to run ddev debug test and capture the output and put it in a gist on gist.github.com, then come over to discord with a link to that.
I have an existing spark-job, the functionality of this spark-job is to connect kafka-server get the data and then storing the data into cassandra tables, now this spark-job is running on server inside spark-2.1.1-bin-hadoop2.7/bin but whenever I am trying to run this spark-job from other location, Its not running, this spark-job contains some JavaRDD related code.
Is there any chance, I can run this spark-job from outside also by adding any dependency in pom or something else?
whenever I am trying to run this spark-job from other location, Its not running
spark-job is a custom launcher script for a Spark application, perhaps with some additional command-line options and packages. Open it, review the content and fix the issue.
If it's too hard to figure out what spark-job does and there's no one nearby to help you out, it's likely time to throw it away and replace with the good ol' spark-submit.
Why don't you use it in the first place?!
Read up on spark-submit in Submitting Applications.
i never really understood how to start a docker and how to maintain it alive.
I have a question, so when you start a docker in the terminal you must provide a command for the docker so it maintains alive, and when you dont provide a service it restarts everytime, you can provide the /bin/bash so it maintains open. (Could you show me how to do it the right way, maintain it open with bash ?)
When it comes to rancher, when you create a new docker you can provide the command too, but if you dont the docker won't restart it maintains alive, so what does this means, that it have default command ? (/bin/bash)? What command does exactly executes rancher to start the docker?
thank you all
It is probably best if you read some about docker, to get the various concepts clear. From your use of "a docker", it seems that you don't really have all the pieces yet for an easy understanding.
A quick layout would be that you have
Image. I have seen this compared to a 'class' in programming
Container. In the same comparison, this would be an object: an instance of a class.
If you want to run something with docker, you start a container from an image. Just like if you want to create an object, you create one from a class. (lets not take this comparison/simili too far)
Now a containers purpose is to run something, rather, to run a single something. So "keeping a docker open" is not something you 'should want' What you want is to run, for instance, a server. Or a script.
Every container runs a single process (or should run one). As the 'official' usecase is not 'create a virtual server you can play around', it might behave strange or complicated if you want to have place to ssh to and not run a specific thing.
This also means you don't want to run any services as a background: if you run apache, you want to run it not as a daemon, but just run it: that's what the docker container is for. If you need to run something else (for instance, a database server) you would start a second container.
There might be exceptions for this, but to get your head around the why stuff works as it does, you should probably start somewhat religiously with these 'rules', and from that point go on.
I know there are about a thousand answers to various permutations of this question but none of the fifteen or so that I've tried have worked.
I'm running on Mac OS Sierra and using Minikube 0.17.1 as well as kubectl 1.5.3.
We run our own private Docker registry that is insecure as it is not open to the internet. (This is not my choice or in my control so it's not open for discussion). This is my first foray into Kubernetes and actually container orchestration altogether. I also have a very intermediate level of knowledge about Docker in general so I'm drowning in terminology/platform soup here.
When I execute
kubectl run perf-ui --image=X.X.X.X/performance/perf-ui:master
I see
image pull failed for X.X.X.X/performance/perf-ui:master, this may be because there are no credentials on this request. details: (Error response from daemon: Get https://X.X.X.X/v1/_ping: dial tcp X.X.X.X:443: getsockopt: connection refused)
We have an Ubuntu box that accesses the same registry (not using Kubernetes, just Docker) that works just fine. This is likely due to
DOCKER_OPTS="--insecure-registry X.X.X.X"
being in /etc/default/docker.
I made a similar change using the UI of Docker for Mac. I don't know where this change persisted in a config file. After this change a docker pull worked on my laptop!!! Again, this is just using Docker not Kubernetes. The interesting part is I got the same "Connection refused error" (as it tries to access via HTTPS) on my Mac as I get in the Minikube VM and after the change the pull worked. I feel like I'm on to something there.
After sshing into minikube (the VM created my minikube start) using
minikube ssh
I added the following content to /var/lib/boot2docker/profile
export EXTRA_ARGS="$EXTRA_ARGS --insecure-registry 10.129.100.3
export DOCKER_OPTS="$DOCKER_OPTS --insecure-registry 10.129.100.3
As you can infer, nothing has worked. I know I've tried other things but they too have failed.
I know this isn't the most comprehensive explanation but I've been digging into this for the past 4 hours.
The bottom line is docker pulls work from our Ubuntu box with the config file setup correctly and from my Mac with the setting configured properly.
How can I enable the same setting in my "Linux 2.6" VM that was created by Minikube?
If someone knows the answer I would be forever grateful.
Thank you in advance!
Thank you to Janos for your alternative solution. I'm confident that is the right choice for some use cases.
It turns out that what I needed was a good night sleep and the following command to start Minikube in the first place:
minikube start --insecure-registry="X.X.X.X"
#intelfx says that adding a port won't be necessary. I'm inclined to believe them but if your registry is on a non-standard port just keep it in mind in case things still aren't working.
In the end it was, in fact, a matter of telling Docker to use an insecure registry but it was not clear how to tell this to Docker when I was not controlling it directly.
I know that seems simple but after you've tried a hundred things you're almost hallucinating so you're not in a great state to make rational decisions. I'm sorry for the dumb post but I'm willing to bet this will help at least one person one day, which makes it worth it.
Thanks SO!
The flag --insecure-registry doesn't work on the existing cluster on MacOS. You need to do minikube delete, it's not enough just to stop the cluster with kubectl stop.
I spent plenty of time to figure this out and then I found this comment at https://github.com/kubernetes/minikube/issues/604:
the --insecure-registry flag is ignored if the
machine already existed (even if it is stopped). You must first
minikube delete if you want new flags to be respected.
You can use kube-registry-proxy from (needs some configuration):
https://github.com/kubernetes/kubernetes/blob/master/cluster/saltbase/salt/kube-registry-proxy/kube-registry-proxy.yaml
Then you can refer to localhost:5050 as your registry. The trick is that localhost is allowed as an insecure registry by default.
I want to run an arbitrary application inside a docker container safely, like within a vm. To do so I save the application (that I donwloaded from the web and that I don't trust) inside a directory of the host system and I create a volume that maps this directory with the home directory of the container and then I run the application inside the container. Are there any security issues with this approach? Are there better solutions to accomplish the same task?
Moreover, to install all the necessary dependencies, I let to execute an arbitrary script inside a bash terminal running inside the container: could this be dangerous?
To add to #Dimitris answer. There are other things you need to consider.
There are certain things container do not contain. Docker uses namespaces to alter process view of the system.i.e N/W Shared memory etc. But you have to keep in mind it is not like KVM. Docker do talk to kernel directly unlike KVM(Vms) like /proc/sys.
So if the arbitrary application tries to access kernel subsystems like Cgroups , /proc/sys , /proc/bus etc. you could be in trouble. I would say its fine unless its a multi-tenant system.
As long as you do not give the application sudo access you should be good to try it out.
Dependencies are better off defined in the Dockerfile in a clear way for other to see. Opting to run a script instead will also do the job but it's more inconvenient.