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Not really. Even in an absolute sense, linux-vserver is/was contemporary with zones. Yes, in the sense that partitioning technology isn't new. zones and jails

by evol262 12y ago

Not really. Even in an absolute sense, linux-vserver is/was contemporary with zones. Yes, in the sense that partitioning technology isn't new. zones and jails are comparable to vserver/openvz/lxc. vpars, lpars, and ldoms have analogues on mainframes. Various hypervisor technologies (xen, kvm, vmkernel) are also not unique to solaris, and were done on Linux. What Docker offers that none of these do not is that it's containerization for applications without the "weight" of even zones. It's not virtualizing systems. It's starting one application in its own container. That's it. I don't know who's spreading this "Docker is just like zones" FUD, but it's wrong. Linux has had container-level virtualization for a decade, and LXC has had mainline support for a while. Docker builds on that, but it's different. At the same time, EMC is not shitting themselves over docker. Application containers will not replace traditional or container virtualization for all workloads. But they will for some.

benjarrell 12y ago
Having never used Docker, if it is containerization for applications, how is it different from Application WPARs or App-V?
- evol262 12y ago
  It's analogous to App-V or an Application LPAR, if such a thing existed, but these are both good examples. My complaint to the previous poster is mostly that it differs in the same way that an Application WPAR differs from a WPAR. Yes, they're the same base. No, they're not the same thing.
binarycrusader 12y ago
Sorry, but I'm going to disagree. linux-vserver is not contemporary with zones. If you think that it is, you haven't looked at Solaris zones technology very carefully. linux-vserver requires the kernel to be patched; Solaris zones does not. linux-vserver has no clustering or process migration capability; Solaris zones in combination with LDOMs gives you a path for live migration. linux-vserver networking is based on isolation, not virtualization. This means each virtual server can't create its own internal routing or firewall setup -- Solaris zones can. linux-vserver doesn't fully virtualize the system; clock, parts of /proc and /sys are not virtualized. So no, linux-vservers are not equivalents. Yes, docker offers containerization -- but not sufficient containerization. Certainly not sufficient for security purposes as have come up repeatedly in recent history. As for the "weight" of zones; I don't know what "weight" you're talking about. Solaris zones have almost no overhead at all. They use some disk space, but we're talking less than 300MB if I recall correctly at most in a default configuration. And Solaris Zones give you several advantages that Docker doesn't provide. Regardless, I'm certain that for some specific use cases, Docker will prove an appropriate technology.
- pstuart 12y ago
  All good, except that Solaris is a ghetto.
  - binarycrusader 12y ago
    All good, except you didn't bother posting anything of meaningful value. In what way, precisely, can Solaris objectively be qualified as what you describe?
    - pstuart 12y ago
      Meaning that while Solaris had many technical advantages over Linux, it's not exactly a vibrant and growing community. Do you really think that any greenfield endeavor is going to pick Solaris as its OS? Disclaimer: I just left a gig where I spent 6 years in a Solaris shop, and while there wrote an on-demand zones management system.
      - deleted 12y ago
        [deleted]
      - binarycrusader 12y ago
        So in other words, your comment really wasn't about Solaris, it was about ecosystem and community. As for "vibrant" or "growing", I don't know how you would objectively measure those things or to what objective metric you would relatively compare them to. Even if the Solaris community is not what you desire, the technology is still certainly significantly advancing almost every year.
- xorcist 12y ago
  This is not something you agree or disgree with. The Linux technologies mentioned _was_ contemporary, or in specific cases even pre-dates, zones. The rest is just not a one-to-one comparison. The fact that Linux requires the kernel to be patched is a cultural thing. That is how new functionality is distributed in Linux land. Linux-vserver also does not, as you mention, offer comparable functionality. Solaris Zones works differently, and the only cases where you can compare them is where their use cases overlap. But you will see much more overlap with something like LXC. Any direct comparion is moot however, as Sun/Oracle does not want these technologies to be adopted in Linux. They can at most serve as (valuable) proof of concepts on how the implementation works in the real world as Linux slowly gains corresponding functionality. And it increasingly looks like Docker is part of this picture.
rdtsc 12y ago
> Docker builds on that, but it's different. So what is different? You wrote whole paragraph about what it isn't. But what is it then that make Docker not just LXC (other container) + scripts to manage applications in it. One could presumable still spawn a single application on any OS...
- evol262 12y ago
  Docker is application containerization. While Docker is built on top of libcontainer and cgroups (used to be LXC), traditional containers, including LXC and zones, start init and enough services to look like a "normal" system. You can still use rc.local to manage applications if you want to, I guess. Docker is a build system for containers which run /bin/foo as PID1, with no services, no ssh, and no init (which presents other problems reaping children, handling sigterm, etc). It's containerization for application virtualization.

by evol262 12y ago

benjarrell 12y ago

Having never used Docker, if it is containerization for applications, how is it different from Application WPARs or App-V?

evol262 12y ago
It's analogous to App-V or an Application LPAR, if such a thing existed, but these are both good examples. My complaint to the previous poster is mostly that it differs in the same way that an Application WPAR differs from a WPAR. Yes, they're the same base. No, they're not the same thing.

binarycrusader 12y ago

Sorry, but I'm going to disagree. linux-vserver is not contemporary with zones. If you think that it is, you haven't looked at Solaris zones technology very carefully. linux-vserver requires the kernel to be patched; Solaris zones does not. linux-vserver has no clustering or process migration capability; Solaris zones in combination with LDOMs gives you a path for live migration. linux-vserver networking is based on isolation, not virtualization. This means each virtual server can't create its own internal routing or firewall setup -- Solaris zones can. linux-vserver doesn't fully virtualize the system; clock, parts of /proc and /sys are not virtualized. So no, linux-vservers are not equivalents. Yes, docker offers containerization -- but not sufficient containerization. Certainly not sufficient for security purposes as have come up repeatedly in recent history. As for the "weight" of zones; I don't know what "weight" you're talking about. Solaris zones have almost no overhead at all. They use some disk space, but we're talking less than 300MB if I recall correctly at most in a default configuration. And Solaris Zones give you several advantages that Docker doesn't provide. Regardless, I'm certain that for some specific use cases, Docker will prove an appropriate technology.

pstuart 12y ago
All good, except that Solaris is a ghetto.
- binarycrusader 12y ago
  All good, except you didn't bother posting anything of meaningful value. In what way, precisely, can Solaris objectively be qualified as what you describe?
  - pstuart 12y ago
    Meaning that while Solaris had many technical advantages over Linux, it's not exactly a vibrant and growing community. Do you really think that any greenfield endeavor is going to pick Solaris as its OS? Disclaimer: I just left a gig where I spent 6 years in a Solaris shop, and while there wrote an on-demand zones management system.
    - deleted 12y ago
      [deleted]
    - binarycrusader 12y ago
      So in other words, your comment really wasn't about Solaris, it was about ecosystem and community. As for "vibrant" or "growing", I don't know how you would objectively measure those things or to what objective metric you would relatively compare them to. Even if the Solaris community is not what you desire, the technology is still certainly significantly advancing almost every year.
xorcist 12y ago
This is not something you agree or disgree with. The Linux technologies mentioned _was_ contemporary, or in specific cases even pre-dates, zones. The rest is just not a one-to-one comparison. The fact that Linux requires the kernel to be patched is a cultural thing. That is how new functionality is distributed in Linux land. Linux-vserver also does not, as you mention, offer comparable functionality. Solaris Zones works differently, and the only cases where you can compare them is where their use cases overlap. But you will see much more overlap with something like LXC. Any direct comparion is moot however, as Sun/Oracle does not want these technologies to be adopted in Linux. They can at most serve as (valuable) proof of concepts on how the implementation works in the real world as Linux slowly gains corresponding functionality. And it increasingly looks like Docker is part of this picture.

rdtsc 12y ago

> Docker builds on that, but it's different. So what is different? You wrote whole paragraph about what it isn't. But what is it then that make Docker not just LXC (other container) + scripts to manage applications in it. One could presumable still spawn a single application on any OS...

evol262 12y ago
Docker is application containerization. While Docker is built on top of libcontainer and cgroups (used to be LXC), traditional containers, including LXC and zones, start init and enough services to look like a "normal" system. You can still use rc.local to manage applications if you want to, I guess. Docker is a build system for containers which run /bin/foo as PID1, with no services, no ssh, and no init (which presents other problems reaping children, handling sigterm, etc). It's containerization for application virtualization.