发布于 2015-09-17 00:56:25 | 155 次阅读 | 评论: 0 | 来源: 网友投递
Rocket CoreOS 的容器引擎
Rocket （也叫 rkt）是 CoreOS 推出的一款容器引擎，和 Docker 类似，帮助开发者打包应用和依赖包到可移植容器中，简化搭环境等部署工作。Rocket 和 Docker 不同的地方在于，Rocket 没有 Docker 那些为企业用户提供的“友好功能”，比如云服务加速工具、集群系统等。反过来说，Rocket 想做的，是一个更纯粹的业界标准。
Rocket 0.8.1 发布，更新内容如下：
该版本一些重大的 UX 变化：
Arguments can now be passed through to CNI plugins on the command line - see the networking documentation for details
The default metadata service port has been changed from 2375 (which had an unfortunate conflict with an IANA registered/reserved port) to an arbitrary non-registered port, 18112
The APPNAME field in the output of rkt image list has been changed to the more accurate NAME
rkt rm now supports a variable number of arguments, allowing the removal of multiple pods simultaneously
完整的更新列表:
New features and UX changes:
rkt rm is now variadic: it can now remove multiple pods in one command, by UUID
The APPNAME column in rkt image list output has been changed to the more accurate NAME. This involves a schema change in rkt's on-disk datastore, but this should be upgraded transparently.
Headers are now sent when following HTTP redirects while trying to retrieve an image
The default metadata service port number was changed from a registered/reserved IANA port to an arbitrary port in the non-dynamic range
Added the ability to override arguments for network plugins
rkt will now error out if someone attempts to use --private-users with the lkvm backend
Bug fixes:
Fixed creation of /tmp in apps' root filesystems with correct permissions
Fixed garbage collection after umounts (for example, if a system reboots before a pod is cleanly destroyed)
Fixed a race in interactive mode when using the lkvm backend that could cause a deadlock or segfault
Fixed bad parameter being passed to the metadata service ("uid" -> "uuid")
Fixed setting of file permissions during stage1 set up
Fixed a potential race condition during simultaneous iptables invocation
Fixed ACI download progress being sent to stderr instead of stdout, now consistent with the output during retrieval of Docker images
rkt help prepare will now show the correct default stage1 image
rkt will refuse to add isolators with nil Limits, preventing a panic caused by an ambiguity in upstream appc schema
Other changes:
Reworked the SELinux implementation to use systemd-nspawn's native context-switching feature
Added a workaround for a bug in Docker <1.8 when it is run on the same system as rkt (see #1210 (comment))
Added a rkt-xxxx-tapN name to tap devices that rkt creates
Functional tests now clean intermediate images between tests
Countless improvements and cleanup to the build system
Numerous documentation improvements, including splitting out all top-level rkt subcommands into their own documents
下载页面：v0.8.1
Rocket （也叫 rkt）是 CoreOS 推出的一款容器引擎，和 Docker 类似，帮助开发者打包应用和依赖包到可移植容器中，简化搭环境等部署工作。Rocket 和 Docker 不同的地方在于，Rocket 没有 Docker 那些为企业用户提供的“友好功能”，比如云服务加速工具、集群系统等。反过来说，Rocket 想做的，是一个更纯粹的业界标准。
CoreOS 把它的容器称为 App Containers，里面包含 app container image、runtime、container-discovery 协议等。其中，App Container Image 和 Docker 里的 Image 比较类似，包含应用必需的元素组成，如源代码和二进制文件。Rocket runtime 则是依照 App Container 标准规格打造的，旨在将容器真正的变成一款命令行工具。