A question that I would have liked to have been asked and answered... and yes, I'm pro-FOSS:
Why do you think that many companies have had so much trouble following Cygnus' and Red Hat's business model and similarly succeeding with it? Why does Red Hat seem to be the leader in a very small pack of open source companies that are profitable? Why do some FOSS companies (*cough*nonical) seem to have a problem becoming profitable?
I realize that commercial / closed software companies also fail more than they succeed and that the top dogs in closed technology are more the exception than the rule.
Are closed and open source companies the same with regards to success? ... that more are doomed to fail than succeed?
Docker, and more generally... containers... do provide virtualization.
I'm a long-time OpenVZ user which is a much older form of containers on Linux dating back to 2005. Originally OpenVZ used the term VE for "virtual environment". It wasn't virtualizing hardware and wasn't a virtual machine but it was virtualizing the environment because your VE could be any one from a reasonable selection of Linux distributions. Then they switched from VE to VPS which is short for Virtual Private Server. I guess VPS tries to emphasize the fact that the VPS has private accounts and runs mostly server applications rather than a desktop. Then container became the preferred term.
All throughout those perhaps marketing-oriented name changes the way a container worked hadn't really changed. A container is a set of grouped processes that are isolated from other processes running on a single kernel... with the ability to set resource limits that apply to them. In OpenVZ's case the isolation was complete enough that each container could have their own accounts/users including root... its own network stack and virtualized pid space. So rather than Hardware Virtualization, containers are OS-level Virtualization.
In the case of KVM, all virtual machines running on a host are just another process running on a single kernel... so the way I look at it, KVM is a type 1.5 hypervisor. Sure, what runs in each process under that same kernel can be a different operating system.
Authored Comments
A question that I would have liked to have been asked and answered... and yes, I'm pro-FOSS:
Why do you think that many companies have had so much trouble following Cygnus' and Red Hat's business model and similarly succeeding with it? Why does Red Hat seem to be the leader in a very small pack of open source companies that are profitable? Why do some FOSS companies (*cough*nonical) seem to have a problem becoming profitable?
I realize that commercial / closed software companies also fail more than they succeed and that the top dogs in closed technology are more the exception than the rule.
Are closed and open source companies the same with regards to success? ... that more are doomed to fail than succeed?
Docker, and more generally... containers... do provide virtualization.
I'm a long-time OpenVZ user which is a much older form of containers on Linux dating back to 2005. Originally OpenVZ used the term VE for "virtual environment". It wasn't virtualizing hardware and wasn't a virtual machine but it was virtualizing the environment because your VE could be any one from a reasonable selection of Linux distributions. Then they switched from VE to VPS which is short for Virtual Private Server. I guess VPS tries to emphasize the fact that the VPS has private accounts and runs mostly server applications rather than a desktop. Then container became the preferred term.
All throughout those perhaps marketing-oriented name changes the way a container worked hadn't really changed. A container is a set of grouped processes that are isolated from other processes running on a single kernel... with the ability to set resource limits that apply to them. In OpenVZ's case the isolation was complete enough that each container could have their own accounts/users including root... its own network stack and virtualized pid space. So rather than Hardware Virtualization, containers are OS-level Virtualization.
In the case of KVM, all virtual machines running on a host are just another process running on a single kernel... so the way I look at it, KVM is a type 1.5 hypervisor. Sure, what runs in each process under that same kernel can be a different operating system.
Containers are still virtualization.