I have installed mongodb on a docker container together with openssh on ubuntu 14.04. The container is running with ssh but when I ssh into the container I get the following error when trying to start mongod.
root#430f9502ba2d:~# service mongod start
Rather than invoking init scripts through /etc/init.d, use the service(8)
utility, e.g. service mongod start
Since the script you are attempting to invoke has been converted to an
Upstart job, you may also use the start(8) utility, e.g. start mongod
Also start mongod does not affect anything.
Tried looking at this also Mongo daemon doesn't run by service mongod start without it helping.
mongod --config /your/path/to/mongod.conf doesn't seem to work also, just locks up.
The error below is standard as of course there is no mongod server running.
root#430f9502ba2d:/# mongo
MongoDB shell version: 2.6.9
connecting to: test
2015-05-07T20:49:56.213+0000 warning: Failed to connect to 127.0.0.1:27017, reason: errno:111 Connection refused
2015-05-07T20:49:56.214+0000 Error: couldn't connect to server 127.0.0.1:27017 (127.0.0.1), connection attempt failed at src/mongo/shell/mongo.js:146
exception: connect failed
The problem here is your approach. Docker does not have an init system like you are used to on traditional systems. What docker does is replace PID 1 with the process you specify in the CMD or ENTRYPOINT Dockerfile commands. For now, ignore ENTRYPOINT, because it replaces what your CMD is run with (normally, it's /bin/sh -c). You need to instruct docker to start your mongod service in your Dockerfile with the CMD command, like:
CMD usr/bin/mongod
And when you run your container, mongod will be your PID 1. Now, you're probably wondering at this point "But what about my SSH server?" and the answer is: Don't run an SSH server on your docker containers. There are some use cases where running an SSH server is okay, but almost all of the "normal" reasons (debug, C&C, etc) are nullified with the "best practice" for getting a shell on your container:
docker exec -it myContainer /bin/bash
This will drop you into a shell on your running container. The recommendation here for managing configuration and changes in your docker container is to use something like Ansible. However, remember that docker containers are ephemeral, and you shouldn't be restarting services and changing configuration state on them. If you need a config change, change the Dockerfile or config data, and then start a new container. Good luck! Here is a little more information on Dockerizing MongoDB, but keep in mind that the method described there alters the ENTRYPOINT in the Dockerfile, which is a little more involved and requires a better understanding of what's going on in Dockerfiles.
This is really helpful. I was trying to make old Ansible playbooks work with Docker by creating several blank containers and let Ansible do the rest.
It works through command
mongod --dbpath /var/lib/mongodb --smallfiles
Related
I'm currently working with Docker, I use mongo image for my DB container. For persistent storage, I mounted host machine's directory(e.g. /var/docker/data/db) to container(e.g. /data/db).
By now, whenever I wanted to run mongo shell and connect to my db I was doing these things:
Attach to running MongoDB container using docker exec -it <container> bash
Run mongo shell inside the container
Do some job
But I think it'll be much better if I could run mongod separately on the host machine, not in the container, and then connect to it even when the container is not running.
So is it possible to doing so? If I run two mongod process on the same directory(files), will there be an file access conflict?
If someone did similar kind of work, share me your experience please. Thanks.
I unable to start MonogoDB service after adding users into admin db as well as my db.
I setup MonogoDB and started service using following command i.e.
service mongod start
Using command prompt, I added few users like dbOwner, clusterAdmin, readWrite, read roles base users. Along with that I also changed configuration from /etc/mongod.conf. in that file, I changed port number, IP addresses, dbPath, and security.authorization: enabled.
Then I restarted mongod service using following command.
service mongod restart
After ran this command, mongod service stopped successfully, but failed to start with only 'FAILED' message.
I tried execute following command i.e.
mongod --port 27123 --dbpath /path/to/db --auth
It is working.
Question: How to execute 'service mongod start' using additional parameters in CentOS?
MonogoDB: 3.4
OS: CentOS 7
I got solution i.e.
mongod --config /etc/mongod.conf
Referred: https://docs.mongodb.com/manual/reference/configuration-options/#use-the-configuration-file
It starts child process and also I can stop mongod service using service mongod stop command.
But I don't know whether it is correct or not.
I can't certify exactly where the script that "service" command uses on CentOS 7, but in Ubuntu 18.04 mongod service script file is in
/lib/systemd/system/mongod.service
There you can change the user who executes the process and add any parameters you want, like --auth.
Said that, if you ever executed mongod as root, some files on where you store the db data will have the owner as root, making the database fail to start as another user. The fix I found for that is to manually chown to mongodb:mongodb (or the user you want to use) all the files that are owned by root inside the database.
Hope this helps.
mongod.service file from mongodb github
I'm new to docker and mongoDB, so I expect I'm missing some steps. Here's what I have in my Dockerfile so far:
FROM python:2.7
RUN apt-get update \
&& apt-get install -y mongodb \
&& rm -rf /var/lib/apt/lists/*
RUN mkdir -p /data/db
RUN service mongodb start
RUN mongod --fork --logpath /var/log/mongodb.log
RUN mongo db --eval 'db.createUser({user:"dbuser",pwd:"dbpass",roles:["readWrite","dbAdmin"]})'
The connection fails on the last command:
Error: couldn't connect to server 127.0.0.1:27017 at src/mongo/shell/mongo.js:145
exception: connect failed`.
How can I connect successfully? Should I change the host/IP, and to what, in which commands?
Several things going wrong here. First are the commands you're running:
RUN service mongodb start
RUN mongod --fork --logpath /var/log/mongodb.log
Each of these will run to create a layer in docker. And once the command being run returns, the temporary container that was started is stopped and any files changed in the container are captured to make a new layer. There are no persistent processes that last between these commands.
These commands are also running the background version of the startup commands. In docker, you'll find this to be problematic since when you use this as your container's command, you'll find the container dies as soon as the command finishes. Pid 1 on the container has the same role of pid 1 on a linux OS, once it dies, so does everything else.
The second issue I'm seeing is mixing data with your container in the form of initializing the database with the last RUN command. This fails since there's no database running (see above). I'd recommend instead to make an entrypoint that configures the database if one does not already exist, and then use a volume in your docker-compose.yml or on your docker run commandline to persist data between containers.
If you absolutely must initialize the data as part of your image, then you can try merging the various commands into a single run:
RUN mongod --fork --logpath /var/log/mongodb.log \
&& mongo db --eval 'db.createUser({user:"dbuser",pwd:"dbpass",roles:["readWrite","dbAdmin"]})'
I think you misunderstood what Dockerfiles are used for.
As Dockerfile reference points out, a
Dockerfile is a text document that contains all the commands a user could call on the command line to assemble an image.
The whole concept of an image is to derive running container from it which are then filled with data and queried (in case of a database) or are beeing called by an external container / host (in case of an web service) or many other possible usages.
To answer your question I'll assume that:
You want to use a mongo database to store data.
You have some pyhton code which needs to have access to mongo.
You want some initial data in your database.
To do so:
Run a mongo database
docker run --name my-mongo -d mongo
Note: There is no need to write a custom image. Use the official mongo image!
Create a python image which contains your script
a) Write your Dockerfile
FROM python:3-alpine
ADD my_script.py /
RUN pip install any-dependency-you-might-need
CMD [ "python", "./my_script.py" ]
b) Write your my_script.py
Insert your application stuff here. It will be executed in the python container. And as mongo will be linked, you can use s.th. like client = MongoClient('mongodb://mongo:27017/') to get started.
Run your python container with a link to mongo
a) Build it:
docker build -t my-pyhthon-magic .
b) Run it:
docker run -d --name python-magic-container --link my-mongo:mongo my-python-magic
Note: The --link here links a running container named my-mongo to be reached internally in my-python-magic-container as mongo. That`s why you can use it in your python script.
I hope this helped you - don't hesitate to ask or modify your question if I misunderstood you.
I have two Azure virtual machines. On one I have a Mongo server, on the other I just have a service I created which listens to Twitters streaming API and filters tweets.
Neither of these two services work unless I manually activate them and keep my console window open. For example, to run Mongo I need to ssh into my virtual machine and type: mongod --config /etc/mongod.conf. This starts the Mongo server successfully, but if at anytime I close my browser the service stops.
I believe the reason this is occurring is because when I login the system is allocating me a process by which I can navigate around the system and perform commands. When I type mongod --config /etc/mongod.conf I believe I am using that process to run Mongo. I am not sure how to make Mongo run without doing this though.
How do I make it so Mongo runs automatically all the time on my Azure server?
EDIT:
I tried running Mongo as a daemon but I receive an error:
$ mongod --fork --logpath /var/log/mongodb.log
>>>about to fork child process, waiting until server is ready for connections.
>>>forked process: 63470
>>>ERROR: child process failed, exited with error number 1
This issue has nothing to do with Azure; it's all about how you install MongoDB.
If you install mongodb as a service, via apt-get (or whatever other means your version of linux requires), then it will run independent of you being logged in. You shouldn't be running an always-on service through your command shell.
Here are instructions for installing under Ubuntu. You'll see that, once you set up the prerequisite public key and list file, you then run:
sudo apt-get install -y mongodb-org
You can then start and stop the service via
sudo service mongod start
and
sudo service mongod stop
You can enable mongo to autostart on boot by typing this command in your console:
sudo systemctl enable mongod
Then test it by this command:
sudo service mongod status
I'm running docker container in OSX using boot2docker. It is a latest Ubuntu image with mongo installed using official way from package mongodb-org.
I can perfectly run mongod from command line, but can't run it as a service.
When I'm trying to do sudo service mongod start it returns
Rather than invoking init scripts through /etc/init.d, use the service(8)
utility, e.g. service mongod start
Since the script you are attempting to invoke has been converted to an
Upstart job, you may also use the start(8) utility, e.g. start mongod
I have tried to do start mongod which doesn't have any output. I have tried everything I found in Google, but no luck.
Meanwhile, I have tried to install MySQL using apt-get and I can perfectly run it as a service.
Also I have tried to install Mongo from Ubuntu's mongodb package which is a older version. Also no problem to run it as a service.
I suspect that there is something wrong with /etc/init.d/mongod script, but don't know exactly what.
Apprieciate any help.
The init-related commands on the Docker Ubuntu image are dummied out / not working because Upstart (/sbin/init) is not the first process started on the machine.
In general, any service which initializes using Upstart will not run properly in a Docker container unless you start the container with /sbin/init (you probably have to be using the ubuntu-upstart image, and make a bunch of tweaks to it too.)
If you really needed to do it this way, write a traditional init script for mongo and insert it using update-rc.d. Then, starting it with /sbin/service should work.
Why not just have the Dockerimage run mongod instead of init/shell/etc? "One process per container", right?
Use a Dockerfile to create your image, and set the CMD to:
CMD ["/usr/bin/mongod", "-f", "/etc/mongod.conf"]