What Are Containers?

hi welcome to this latest episode of light board lessons and today we're gonna talk about containers and what containers are and some of the benefits of them and so if you look at where we've gone with virtualization and and you know the whole point is is to have some layer of abstraction and so if we look at traditional virtual machines you have your say this is a server it could be a desktop but you have your infrastructure layer and you have your host operating system okay and then with a virtual server environment you have this hypervisor layer now this could be a type one or a type 2 hypervisor so whether it's on bare metal or running on another operating system you have choices on your hypervisors and then you have your guest operating systems so in any one particular virtual machine if this is the m1 v m2 and DM 3 you could have Windows running here you could have BSD running here Linux running here and and so on and so forth and then on top of your operating system you have your your your binaries your libraries so you have that across-the-board binary library lair and of course you have your applications so any if it's about isolation and you're trying to isolate your applications then on VM one you would have app 1 and then a 2 and app three and and so this is the this is the VM world okay and then you have a the container options and let's come over here for that one and we can go kind of the same overall picture here that the first two layers are the same you have infrastructure and you have your host OS and then the difference here is instead of a hypervisor you have your container runtime and so you know that might be here your docker Damon or LXE Damon's or whatever but this is your your container daemon whatever's controlling the processes for your container environment and so here instead of having your guest OS layer here you're gonna use the host OS and and share it amongst your environments and so the difference here is that you end up with fairly lightweight containers that can use everything in the host OS so your your binary oh that's terrible make that a little bigger so you can read it so your binaries and libraries are going to be specific to the application that you're running like you would deploy in a virtual machine but now packaged just for the use of the application but with direct host OS access for for shared resources and so again app one is here and app two and app three and of course we say app one that could be a micro service of a much larger application suite and that's actually one of the big benefits of containers is its modularity so if we're looking at the differences between these two and you can take this entire container if we take this let me use a different color here you could take all of this and you could drop that whole thing into one of these guest OS virtual machine and then put apps one two and three in a containerized environment on a single VM if you wanted to go crazy and you know from a development perspective a lot of people do that they'll have virtual machines that then they use to build out their their container systems but so if we're looking at the differences here virtual machines are abstracting the physical hardware turning you know one server into many servers if we're looking at this we're not making this more than one server it's still just one server we're just container izing the applications so that we're packaging code and dependencies but that's it everything else is shared and so if we're looking at size you know a container you're looking at a scale of megabytes whereas with virtual machines you're looking at the scale of gigabytes because it's got to have the entire host OS involved and whereas virtual machine is going to be faster than iron they're slow slow ramp for start-up and and this is you know near instantaneous talking a couple micro milling and it's up and so you know some of the other things that benefits that you can look at between them you know you've got the small disc size low overhead fastboot the modularity that I was talking about in that you could have an app on a container but you might have your database running in one container and your app running in the other and and so if you look at patching traditionally if you're in the mindset of virtual machines you're like oh well I've got to I've got to back up that that virtual machine and run those nightly backups so if anything fails I can redeploy the virtual machine from back up and in patching I'm gonna patch that instance in a container world you're not doing any of that you you really nuke pave you nuke a container that you have running and you pave it with whatever you updated so you're a container image is what you're gonna update so any kind of hatches any kind of feature enhancements and all that they're gonna be updated here and then you just deploy and then you you kill these and and deploy new ones so in a nutshell that's what containers are it's it's just little little containers and and and the binaries and libraries dependent for that application and so you don't have to worry about if I'm on my desktop and I've got Python 2.7 and if I deploy to a server out there in production and it might be on Python 36 and now everything doesn't work you don't have to worry about that because your container image is going to detail all of the necessary packages that you need for your app to run and and and so once that image is defined you deploy image in it and it's good to go so real short real brief any questions you have drop them in the comments and if you enjoyed this video make sure you subscribe to our Channel and we'll see out there in the community you

Channel: F5 DevCentral

Views: 47,361

Rating: 4.9144144 out of 5

Keywords: f5, devcentral, lightboard, containers

Id: wuhxSLapDe0

Length: 8min 38sec (518 seconds)

Published: Mon Mar 26 2018