commit | 27dd48f6919a9bf8c25b41e97ca12f6fa73f8f77 | [log] [tgz] |
---|---|---|
author | Michael Crosby <crosbymichael@gmail.com> | Fri Feb 19 19:23:30 2016 |
committer | Michael Crosby <crosbymichael@gmail.com> | Fri Feb 19 19:23:30 2016 |
tree | d736c04a45a500a14b1dfe0fa8fcc37ea9cf5caf | |
parent | 3d8a20bb772defc28c355534d83486416d1719b4 [diff] |
Move the process outside of the systemd cgroup If you don't move the process out of the named cgroup for systemd then systemd will try to delete all the cgroups that the process is currently in. Signed-off-by: Michael Crosby <crosbymichael@gmail.com>
runc
is a CLI tool for spawning and running containers according to the OCF specification.
Currently runc
is an implementation of the OCI specification. We are currently sprinting to have a v1 of the spec out. So the runc
config format will be constantly changing until the spec is finalized. However, we encourage you to try out the tool and give feedback.
How does runc
integrate with the Open Container Initiative Specification? runc
depends on the types specified in the specs repository. Whenever the specification is updated and ready to be versioned runc
will update its dependency on the specs repository and support the update spec.
At the time of writing, runc only builds on the Linux platform.
# create a 'github.com/opencontainers' in your GOPATH/src cd github.com/opencontainers git clone https://github.com/opencontainers/runc cd runc make sudo make install
In order to enable seccomp support you will need to install libseccomp on your platform. If you do not with to build runc
with seccomp support you can add BUILDTAGS=""
when running make.
runc
supports optional build tags for compiling in support for various features.
Build Tag | Feature | Dependency |
---|---|---|
seccomp | Syscall filtering | libseccomp |
selinux | selinux process and mount labeling | |
apparmor | apparmor profile support | libapparmor |
You can run tests for runC by using command:
# make test
Note that test cases are run in Docker container, so you need to install docker
first. And test requires mounting cgroups inside container, it's done by docker now, so you need a docker version newer than 1.8.0-rc2.
You can also run specific test cases by:
# make test TESTFLAGS="-run=SomeTestFunction"
To run a container, execute runc start
in the bundle's root directory:
runc start / $ ps PID USER COMMAND 1 daemon sh 5 daemon sh / $
OCI container JSON format is based on OCI specs. You can generate JSON files by using runc spec
, it'll generate config.json
and runtime.json
. It assumes that the file-system is found in a directory called rootfs
and there is a user with uid and gid of 0
defined within that file-system.
Below are sample config.json
and runtime.json
configuration files. Note that it could be outdated, please always create base JSON files by runc spec
.
config.json
:
{ "version": "0.2.0", "platform": { "os": "linux", "arch": "amd64" }, "process": { "terminal": true, "user": { "uid": 0, "gid": 0, "additionalGids": null }, "args": [ "sh" ], "env": [ "PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin", "TERM=xterm" ], "cwd": "" }, "root": { "path": "rootfs", "readonly": true }, "hostname": "shell", "mounts": [ { "name": "proc", "path": "/proc" }, { "name": "dev", "path": "/dev" }, { "name": "devpts", "path": "/dev/pts" }, { "name": "shm", "path": "/dev/shm" }, { "name": "mqueue", "path": "/dev/mqueue" }, { "name": "sysfs", "path": "/sys" }, { "name": "cgroup", "path": "/sys/fs/cgroup" } ], "linux": { "capabilities": [ "CAP_AUDIT_WRITE", "CAP_KILL", "CAP_NET_BIND_SERVICE" ] } }
runtime.json
:
{ "mounts": { "cgroup": { "type": "cgroup", "source": "cgroup", "options": [ "nosuid", "noexec", "nodev", "relatime", "ro" ] }, "dev": { "type": "tmpfs", "source": "tmpfs", "options": [ "nosuid", "strictatime", "mode=755", "size=65536k" ] }, "devpts": { "type": "devpts", "source": "devpts", "options": [ "nosuid", "noexec", "newinstance", "ptmxmode=0666", "mode=0620", "gid=5" ] }, "mqueue": { "type": "mqueue", "source": "mqueue", "options": [ "nosuid", "noexec", "nodev" ] }, "proc": { "type": "proc", "source": "proc", "options": null }, "shm": { "type": "tmpfs", "source": "shm", "options": [ "nosuid", "noexec", "nodev", "mode=1777", "size=65536k" ] }, "sysfs": { "type": "sysfs", "source": "sysfs", "options": [ "nosuid", "noexec", "nodev" ] } }, "hooks": { "prestart": null, "poststart": null, "poststop": null }, "linux": { "uidMappings": null, "gidMappings": null, "rlimits": [ { "type": "RLIMIT_NOFILE", "hard": 1024, "soft": 1024 } ], "sysctl": null, "resources": { "disableOOMKiller": false, "memory": { "limit": 0, "reservation": 0, "swap": 0, "kernel": 0, "swappiness": -1 }, "cpu": { "shares": 0, "quota": 0, "period": 0, "realtimeRuntime": 0, "realtimePeriod": 0, "cpus": "", "mems": "" }, "pids": { "limit": 0 }, "blockIO": { "blkioWeight": 0, "blkioLeafWeight": 0, "blkioWeightDevice": null, "blkioThrottleReadBpsDevice": null, "blkioThrottleWriteBpsDevice": null, "blkioThrottleReadIOPSDevice": null, "blkioThrottleWriteIOPSDevice": null }, "hugepageLimits": null, "network": { "classId": "", "priorities": null } }, "cgroupsPath": "", "namespaces": [ { "type": "pid", "path": "" }, { "type": "network", "path": "" }, { "type": "ipc", "path": "" }, { "type": "uts", "path": "" }, { "type": "mount", "path": "" } ], "devices": [ { "path": "/dev/null", "type": 99, "major": 1, "minor": 3, "permissions": "rwm", "fileMode": 438, "uid": 0, "gid": 0 }, { "path": "/dev/random", "type": 99, "major": 1, "minor": 8, "permissions": "rwm", "fileMode": 438, "uid": 0, "gid": 0 }, { "path": "/dev/full", "type": 99, "major": 1, "minor": 7, "permissions": "rwm", "fileMode": 438, "uid": 0, "gid": 0 }, { "path": "/dev/tty", "type": 99, "major": 5, "minor": 0, "permissions": "rwm", "fileMode": 438, "uid": 0, "gid": 0 }, { "path": "/dev/zero", "type": 99, "major": 1, "minor": 5, "permissions": "rwm", "fileMode": 438, "uid": 0, "gid": 0 }, { "path": "/dev/urandom", "type": 99, "major": 1, "minor": 9, "permissions": "rwm", "fileMode": 438, "uid": 0, "gid": 0 } ], "apparmorProfile": "", "selinuxProcessLabel": "", "seccomp": { "defaultAction": "SCMP_ACT_ALLOW", "architectures": null, "syscalls": [] }, "rootfsPropagation": "" } }
To test using Docker's busybox
image follow these steps:
docker
and download the busybox
image: docker pull busybox
docker export $(docker create busybox) > busybox.tar
mkdir rootfs tar -C rootfs -xf busybox.tar
config.json
and runtime.json
by using runc spec
.runc start
and you should be placed into a shell where you can run ps
:$ runc start / # ps PID USER COMMAND 1 root sh 9 root ps
To use runc with systemd, you can create a unit file /usr/lib/systemd/system/minecraft.service
as below (edit your own Description or WorkingDirectory or service name as you need).
[Unit] Description=Minecraft Build Server Documentation=http://minecraft.net After=network.target [Service] CPUQuota=200% MemoryLimit=1536M ExecStart=/usr/local/bin/runc start Restart=on-failure WorkingDirectory=/containers/minecraftbuild [Install] WantedBy=multi-user.target
Make sure you have the bundle's root directory and JSON configs in your WorkingDirectory, then use systemd commands to start the service:
systemctl daemon-reload systemctl start minecraft.service
Note that if you use JSON configs by runc spec
, you need to modify config.json
and change process.terminal
to false so runc won‘t create tty, because we can’t set terminal from the stdin when using systemd service.