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GeneralRe: "Docker" Pin
Nathan Minier22-Aug-18 9:16
professionalNathan Minier22-Aug-18 9:16 
GeneralRe: "Docker" Pin
dandy7222-Aug-18 14:11
dandy7222-Aug-18 14:11 
GeneralRe: "Docker" Pin
Nathan Minier23-Aug-18 1:56
professionalNathan Minier23-Aug-18 1:56 
GeneralRe: "Docker" Pin
dandy7223-Aug-18 5:03
dandy7223-Aug-18 5:03 
GeneralRe: "Docker" Pin
Nathan Minier23-Aug-18 5:45
professionalNathan Minier23-Aug-18 5:45 
GeneralRe: "Docker" Pin
dandy7223-Aug-18 10:53
dandy7223-Aug-18 10:53 
GeneralRe: "Docker" Pin
Kornfeld Eliyahu Peter22-Aug-18 10:45
professionalKornfeld Eliyahu Peter22-Aug-18 10:45 
GeneralRe: "Docker" Pin
kalberts23-Aug-18 3:29
kalberts23-Aug-18 3:29 
I never understood why a large fraction of Docker buffs shows panic reactions every time someone suggests that Docker is a kind of virtualization. Of course there are things that, say, VMware will do that Docker won't do - and the other way around. So Docker isn't identical to VMware.

Yet, the concept of virtualization has been applied in lots of other ways. VMware is not The Only Defintion of virtualization. When I on my Windows machine run a Ubuntu application in a Docker container, operating in its own network world, and sees a Unix style file system rather than the physical NTFS file system underneath - of course those are examples of virtualization!

It seems to me like Docker buffs really are trying to say: Forget about competing alternatives - this is something completely different. You shouln't even consider making any feature-by-feature comparison, because they are so different. Virtualization is out. Containers provide an operating environment which is independent of the underlaying hardware, and that isn't virtualization. You can run different base layers (e.g. different OS kernels) in simultaneously running containers on a single host, but that isn't virtualization. You can create multiple fully independent networks for groups of containers to communicate among themselves; these networks have separate, independent network address spaces so they don't interfere with each other even if they use identical addresses, but that isn't virutalization. Multiple containers running from the same image have identical local file systems at startup, but if they make modifications, one container's changes is invisible to the other containers, even with identical file names, but that isn't virtualization.

We have decided to use a different terminology - we refer to the local file system as a "union FS" to mark a distance from a virtual file system. We call it a "named" network to distinguish it from a virtual network. Hey, they have different names, how could they then represent similar concepts?

Docker containers realize one set of virtualization concepts, VMware another one. It sure seems to me that Docker has made a great selection for a fairly lightweight kind of virtualization. Nevertheless it is creating virtual environments, virtual resources and mapping these onto more or less arbitrary physical hardware. Just like all virtualization does.

Because Docker essentially ignores all other I/O-facilities than IP and Unix-style file systems, it has a somewhat easier job than those VMs taking the full responsibility for I/O (and other hardware access). So Docker can say "Why do /xxx/ to provide a virtual resource - Docker doesn't need it?" Sure, when you do not provide e.g. general I/O, then you don't need it. Still you are virtalizing those resources that you do provide!

I think Docker is great for a large subset of tasks. But why should it displace other virtualization methods for other tasks? Docker is not universal: It cannot handle arbitrary I/O. It cannot handle arbitrary OSes - the base layer (usually an OS kernel) has a rather limited set of APIs to the host for realizing its own provisions, in particular with respect to I/O and device access. Say, if you need to run one container providing a Windows GUI, one running a MacOS application an a few running Linux applications, the Linux Docker implementation cannot handle the two first ones. VMware can. So for that use, why shouldn't I "be allowed to" run VMware?

This seems to me very much as a turf war, were terms and definitions are used a mechanisms to push competitors away. If Docker could take over all tasks, it could make more sense, but since there are lots of issues Docker cannot handle, it will never fully replace VMs, only a certain fraction of them. So why not make clear where Docker is suitable, and leave it at that?
AnswerRe: "Docker" PinPopular
F-ES Sitecore22-Aug-18 2:09
professionalF-ES Sitecore22-Aug-18 2:09 
AnswerRe: "Docker" Pin
Mike Hankey22-Aug-18 2:45
mveMike Hankey22-Aug-18 2:45 
AnswerRe: "Docker" Pin
RickZeeland22-Aug-18 2:46
mveRickZeeland22-Aug-18 2:46 
AnswerRe: "Docker" Pin
Richard Deeming22-Aug-18 3:23
mveRichard Deeming22-Aug-18 3:23 
AnswerRe: "Docker" Pin
kmoorevs22-Aug-18 4:15
kmoorevs22-Aug-18 4:15 
AnswerRe: "Docker" Pin
Kevin Marois22-Aug-18 4:54
professionalKevin Marois22-Aug-18 4:54 
AnswerRe: "Docker" Pin
GKP199222-Aug-18 4:59
professionalGKP199222-Aug-18 4:59 
AnswerRe: "Docker" Pin
MadMyche22-Aug-18 6:13
professionalMadMyche22-Aug-18 6:13 
AnswerRe: "Docker" Pin
Dar Brett22-Aug-18 16:37
Dar Brett22-Aug-18 16:37 
AnswerRe: "Docker" Pin
kalberts23-Aug-18 0:22
kalberts23-Aug-18 0:22 
AnswerRe: "Docker" Pin
DerekT-P23-Aug-18 0:26
professionalDerekT-P23-Aug-18 0:26 
AnswerRe: "Docker" Pin
Greg Lovekamp23-Aug-18 3:23
professionalGreg Lovekamp23-Aug-18 3:23 
AnswerRe: "Docker" Pin
MSBassSinger23-Aug-18 5:06
professionalMSBassSinger23-Aug-18 5:06 
AnswerRe: "Docker" Pin
Matt McGuire23-Aug-18 6:40
professionalMatt McGuire23-Aug-18 6:40 
AnswerRe: "Docker" Pin
Kirk 1038982123-Aug-18 8:25
Kirk 1038982123-Aug-18 8:25 
JokeThe papal visit to Dublin Pin
Duncan Edwards Jones22-Aug-18 0:17
professionalDuncan Edwards Jones22-Aug-18 0:17 
GeneralRe: The papal visit to Dublin Pin
CodeWraith22-Aug-18 0:23
CodeWraith22-Aug-18 0:23 

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