Which of these methods is correct?
One db container for each app
One db container for all apps
Install db without docker
I tried to find information, but nothing. Or I badly searched?
It is immature, but that doesn't seem to be stopping a lot of people using Docker for persistence.
The official Postgres image has 4.5 million pulls - Ok, this doesn't mean that all those images/containers are being used but it does suggest that it is a popular solution.
If you have already decided that you would like to use Docker, because of what containers can offer your architecture, then I don't think you will have trouble using it for persistence - assuming you are happy learning Docker.
I'm using Postgres and MySql in several projects quite successfully on Docker.
In choosing option 1 or 2, I would say that unless your apps are related to the same problem domain/company/project I would go with option 1. Of course, running costs will possibly factor in as well.
I generally go with option 1.
All 3 options could be valid but it depends on the use you have to perform.
In my server I've 1 container for every main postgresql releases currently I use.
I run all of them on different ports (use not random number for ports but some easy to remember because a problem with docker is remember all port numbers and other for every container).
pg84(port 8432), pg93(port 9332), pg94 (port 9432)
I link the pgXX to the container I need and that's perfect for me.
For my experience I prefer option 2 so.
Related
I have two applications, each of which use several databases. Before the days of Docker, I would have just put all the databases on one host (due to resource consumption associated with running multiple physical hosts/VMs).
Logically, it seems to me that separating these into groups (1 group of DBs per application) is the right thing to do and with containers the overhead is low and this seems possible. However, I have not seen this use case. I've seen multiple instances of containerized Postgres running so as to maintain multiple versions (hence different images).
Is there a good technical reason why people do not do this (two or more containers of PostgreSQL instances using the same image for purposes of isolating groups of DBs)?
When I tried to do this, I ran into errors having to do with the second instance trying to configure the postgres user. I had to pass in an option to ignore migration errors. I'm wondering if there is a good reason not to do this.
Well, I am not used to work with prosgresql but with mysql, sqlite and ms sql - and docker, of course.
When I entered docker I used to read a lot about microservices, developing of these and, of course, the devops ideas behind docker and microsoervices.
In this world I would absolutly prefer to have 2 containers of the same base image with a multi stage build and / or different env-files to run you infrastructure. Docker is not only allowing this, it is prefering this.
I'm not sure if this is the right StackExchange to be asking this, but I'm in the process of setting up a MEAN stack application and I want to do it right from the get-go.
I really would like to use Docker and Heroku (due to their new pipelining groups and ease of deployment as the sole developer), but I can't find any guides on how to run MongoDB as a docker image on Heroku.
Is this even possible? I also don't really understand how you can put a database into a binary image (Docker image) anyways, yet every guide I've read says to separate the micro-services.
Has anyone else done this?
Thanks.
EDIT: Or is it just a better idea to leave Mongo undockerized and use MongoLabs and have two separate instances for Dev/Prod databases?
There is an official mongodb docker image which you can use. you just need to make sure you have docker installed on heroku.
If you are concerned about the data persistance you can easily mount host directories into your container so you will have physical access to your data. if you are worried about accebility you can easily expose ports inside your comtainer to your host so everything can connect to it.
Having your database in a container makes you able to be worried only on the db configuration and not the ehole stack . so when something goes down you always know where to look.
I am trying to run Wildfly, Jenkins and Postgresql in Docker container(s).
As far as I could understand from articles I've read, the Docker way is to have each application run in a different container.
Is my assumption correct or is it better to have only one container containing these three applications?
Afaik the basic philosophy behind docker is to run one service per container. You can run whole application inside a container, but I don't think that will go well with the way docker work. Running different services in different containers gives you more flexibility and a better modularity for your app.
How can i run mongo 2.6 and mongo 3.0 at the same time on my linux system ?
I need this because i have 2 projects one is working on mongo 2.6 and one is working on mongo 3.0
Any help is appreciated !!
If you really wan to do this, and I recommend you DO NOT, then the best way is to use a container tech, docker can work quite well or LXC or one of the others.
However, do note that there is a high chance that if your sever is in the "cloud" it is already vitualised as it is as such you will constantly be losing power and resources due to sub virtualising everything over and over.
DO NOT put them on the same host without some kind of separation there will be a high chance of resource contention and conflict that tools like ulimit just cannot solve (well, technically it could but it will be a hairball).
In relational databases I would just pop in W3Schools tutorial, install mysql in my machine and start practicing! How can I learn non relational databases in a similar way? In most tutorials I read that these databases work with multiple nodes and data centers.
Does this mean that I will be unable to learn and practice, say Cassandra, using my own single pc?
You do it just like you do it with mySQL: You set up a database on your local machine and start experimenting.
Most database systems which focus on sharding and clustering also work as a stand-alone instance. But when you want to test these features specifically, you can often run multiple instances on the same machine. When you also want to try how they behave when they run on different machines, you can use a virtualization software like VMWare or VirtualBox to set up a bunch of virtual machines and build your virtual datacenter on your desktop.
(I would recommend VMWare for business use and VirtualBox for home use)
I'm a big fan of MongoDB. It's the NoSQL equivalent of MySQL.
Go to the Try It Out link on their home page and you can actually use it in a live session on their website - no download, no configuration, no hassle! Just use it and learn the basics.
Here's the quick start for Cassandra. http://wiki.apache.org/cassandra/GettingStarted
I don't see any reason you couldnt run that from local host. I think the point is that you Can scale these nosql solutions. Might want to check out mongodb or couchdb as well. Easy set up and both are great nosql solutions in my experience.
I would strongly suggest using something like Amazon EC2 for testing NoSQL solutions. You can definitely install a technology like MongoDB locally and create a replica set, but you should definitely put these on different physical machines if you can.
I have installed things like AppFabric, Couchbase and Mongo locally and created clusters and they always work really well locally. It's very easy because the networking part of it always goes smoothly.
Once you introduce two physical machines and a stronger network partition things get difficult.
You can create instances on EC2 for free last I checked if you use their Micro instances. You'll learn a lot.