Ask HN: Why use Docker and what are the business cases for using it? • Hacker News Board

Re: Ask HN: Why use Docker and what are the business cases for using it?

#11

Post by thebigspacefuck » Tue, Jun 30, 2015, 2:06 PM UTC

Makes system administration somewhat easier since the host OS can stay the same and docker containers change, while giving developers more control. I have total control of which version of packages is installed, which OS I'm using. I don't have to create a ticket, argue over the ask, and get approval just to change an web server timeout. It sort of usurps the sys admin role, though, which might be a negative. I can move my container anywhere that's running Docker and all packages are there inside of the container. If you spend a lot of time setting up new boxes, that's a plus. Before, I had to dump all packages, figure out which ones were missing, then install all of them, and the host OS had to be exactly the same. Now I know it's exactly the same, all the time, anywhere.

My only warning is that using anything but Ubuntu for your build host is going to take way too long and you're going to be waiting hours for it to complete if you don't have any layers cached.

Re: Ask HN: Why use Docker and what are the business cases for using it?

#12

Post by dmarg » Tue, Jun 30, 2015, 2:07 PM UTC

scraymer wrote: post #10

Maybe you have looked already and it wasn't useful to you but on the Docker website it has some pretty good marketing to explain its usefulness: https://www.docker.com/whatisdocker Why Use Docker: "How does this help you build better software? When your app is in Docker containers, you don’t have to worry about setting up and maintaining different environments or different tooling for each language. Focus on creating…

Yeah, I looked at the Docker website. I feel that Docker is super good at marketing and wanted to get some other opinions.

Re: Ask HN: Why use Docker and what are the business cases for using it?

#13

Post by dmarg » Tue, Jun 30, 2015, 2:08 PM UTC

rehevkor5 wrote: post #7

Have you ever used provisioning software like Chef to prepare a server to run your software? Have you ever used that in conjunction with Vagrant in order to test out your provisioning and software deployment locally? Docker replaces (or can replace) all of that.

I have not, as I am fairly new to this field but that makes sense in a way if it can minimize the use of other tools to just use the one tool.

Re: Ask HN: Why use Docker and what are the business cases for using it?

#14

Post by dmarg » Tue, Jun 30, 2015, 2:11 PM UTC

deftek wrote: post #4

I would keep an eye on this project: http://www.opencontainers.org/

Heard about this and seems like everyone and their mother are signing on. This is one of the reasons why I asked the main question is because I want to fully understand what the business case is for using Docker.

Re: Ask HN: Why use Docker and what are the business cases for using it?

#15

Post by vruiz » Tue, Jun 30, 2015, 2:12 PM UTC

Side question. I'm well aware of the benefits of docker but, has anybody measured performance degradation due to lack of machine specialization? Back in the web 1.0 days it was common knowledge that you start in 1 server, then you split into 1 app server and 1 database server and you can get 4x the capacity. Did we lose all that with the docker way? Is it not so relevant anymore with modern multicore CPUs?

Re: Ask HN: Why use Docker and what are the business cases for using it?

#16

Post by b00gizm » Tue, Jun 30, 2015, 2:12 PM UTC

I absolutely love it (Docker + docker-compose) for creating homogenous local development environments. And if your app needs a MongoDB, Elasticsearch or anything else, it's as easy as adding one line to your overall docker-compose config file to link those services to your app. No need to pollute your development machine, you can just have anything running in Docker containers and share them across your team.

I've created several repos on Github for that matter. Here's for example some boilerplate for running Node.js, Express, Nginx, Redis and Grunt/Gulp inside Docker containers:

https://github.com/b00giZm/docker-compose-nodejs-examples

Re: Ask HN: Why use Docker and what are the business cases for using it?

#17

Post by fu86 » Tue, Jun 30, 2015, 2:12 PM UTC

We have a shitload of servers running CentOS for historical reasons. We can't change the distribution because all the services running on this servers are tight to the quirks and special cases of this distribution. So we need to live with CentOS.

Some of our newer services need a up to date version of glibc and a lot of other dependencies CentOS can't provide. So we use docker to boot up Ubuntu 14.04 containers and run the services with special needs in them.

Another great thing is isolating scripts we don't trust. We allow our customers to run scripts of all kind on our servers --> inside Docker containers. So the customers can't mess with the hostsystem.

Re: Ask HN: Why use Docker and what are the business cases for using it?

#18

Post by rubiquity » Tue, Jun 30, 2015, 2:13 PM UTC

rehevkor5 wrote: post #7

Have you ever used provisioning software like Chef to prepare a server to run your software? Have you ever used that in conjunction with Vagrant in order to test out your provisioning and software deployment locally? Docker replaces (or can replace) all of that.

Docker does NOT replace configuration management tools like Chef, Puppet and Ansible. Those are still necessary for preparing the host machine which Docker containers will run on. Where Docker does alleviate/reallocate some things is in the configuration of the containers that run on those hosts. Instead of configuring the host for Ruby/Python/etc. you would move that configuration to your Dockerfile. But I think CM tools also have support for generating Dockerfiles, so there's that too.

Re: Ask HN: Why use Docker and what are the business cases for using it?

#19

Post by vsaen » Tue, Jun 30, 2015, 2:14 PM UTC

simplest case is that it can serve as a multiple staging environment, when you have loads of APP in a single code base (often startups going about prod-market fit). With docker tech shipping speed= production speed. Without docker you are slowed down by 2x or more.Without docker, either you set up a lot of staging environments, which is not great and costly. Or you use one single testing environment and let each of you tech person wait for hours, wasting time, while QA tries to test one branch and you have another idiot deploying another brand on staging. While there are more complex/useful cases, this is one simple biz value i get out of it for my team.

Re: Ask HN: Why use Docker and what are the business cases for using it?

#20

Post by collyw » Tue, Jun 30, 2015, 2:15 PM UTC

To tell all the cool kids you are using it.

(Ok, I know there are real use cases for Docker, but I see a lot of hype as well. People telling my mathematician friend that she needs to use docker at the start of her project - it is likely to be a one off graph she needs to produce for a research paper).