LXC是Linux Containers的缩写，是linux内核自带的容器化工具，用于进程隔离，namespace隔离，文件系统隔离。提供一种轻量的虚拟化解决方案。
本文的操作基于的Ubuntu系统。
安装LXC
Ubuntu下直接安装
$ sudo apt-get install lxc lxc-templates wget bridge-utils
安装完成后查看配置情况
# lxc-checkconfig
Kernel configuration not found at /proc/config.gz; searching...
Kernel configuration found at /boot/config-4.10.0-33-generic
--- Namespaces ---
Namespaces: enabled
Utsname namespace: enabled
Ipc namespace: enabled
Pid namespace: enabled
User namespace: enabled
Warning: newuidmap is not setuid-root
Warning: newgidmap is not setuid-root
Network namespace: enabled
--- Control groups ---
Cgroup: enabled
Cgroup clone_children flag: enabled
Cgroup device: enabled
Cgroup sched: enabled
Cgroup cpu account: enabled
Cgroup memory controller: enabled
Cgroup cpuset: enabled
...
启动LXC container
$ lxc-start -n centos_lxc
配置LXC网络
配置桥接网络
TODO
利用默认模板创建新的container
查看一下当前可用的模板
$ ls /usr/share/lxc/templates/
lxc-alpine lxc-archlinux lxc-centos lxc-debian lxc-fedora lxc-openmandriva lxc-oracle lxc-slackware lxc-sshd lxc-ubuntu-cloud
lxc-altlinux lxc-busybox lxc-cirros lxc-download lxc-gentoo lxc-opensuse lxc-plamo lxc-sparclinux lxc-ubuntu
利用可用的模板创建一个centos的容器
$ sudo lxc-create -n centos_lxc -t centos
命令中
- -n 后面的参数是新创建的container的名字
- -t 后面的参数是创建container所用的模板的名字
创建完成后，利用工具lxc-ls可以查看当前建立的container
$ lxc-ls
centos_lxc sshd-lxc ubuntu_lxc
新建立的container的文件系统保存在目录/var/lib/lxc/<container>/rootfs下面，同时还有一个配置文件config
$ cat config
# Template used to create this container: /usr/share/lxc/templates/lxc-centos
# Parameters passed to the template: -R 7 -a x86_64
# Template script checksum (SHA-1): 85868977b29d63f5ada56fd0d3a138854d0b5eff
# For additional config options, please look at lxc.container.conf(5)
# Uncomment the following line to support nesting containers:
#lxc.include = /usr/share/lxc/config/nesting.conf
# (Be aware this has security implications)
lxc.network.type = veth
lxc.network.link = lxcbr0
lxc.network.hwaddr = fe:e9:10:40:1a:93
lxc.network.flags = up
lxc.rootfs = /var/lib/lxc/centos_lxc/rootfs
lxc.rootfs.backend = dir
# Include common configuration
lxc.include = /usr/share/lxc/config/centos.common.conf
lxc.arch = x86_64
lxc.utsname = centos_lxc
# When using LXC with apparmor, uncomment the next line to run unconfined:
#lxc.aa_profile = unconfined
# example simple networking setup, uncomment to enable
#lxc.network.type = veth
#lxc.network.flags = up
#lxc.network.link = lxcbr0
#lxc.network.name = eth0
# Additional example for veth network type
# static MAC address,
#lxc.network.hwaddr = 00:16:3e:77:52:20
# persistent veth device name on host side
# Note: This may potentially collide with other containers of same name!
#lxc.network.veth.pair = v-centos_lxc-e0
常用工具
- lxc-ls
查看container的详细信息
$ lxc-ls -f
NAME STATE AUTOSTART GROUPS IPV4 IPV6
centos_lxc RUNNING 0 - 10.0.3.33 -
sshd-lxc STOPPED 0 - - -
ubuntu_lxc STOPPED 0 - - -
- lxc-info
查看某一个正在运行的container的详细信息
$ lxc-info -n centos_lxc
Name: centos_lxc
State: RUNNING
PID: 4139
IP: 10.0.3.33
CPU use: 0.87 seconds
...
- lxc-stop
停止一个container
$ lxc-stop -n centos_lxc
- lxc-console
进入一个container的控制台
$ lxc-console -n centos_lxc
Clone Container
从一个已经创建好的container克隆出一个新的来
$ lxc-clone -n centos_lxc -N centos_server
查看克隆好的新的lxc container
$ lxc-ls
centos_client centos_lxc centos_server sshd-lxc ubuntu_lxc
给container分配资源
修改config文件，通过添加一行配置修改cpu分配，例如分配了CPU 0给container
lxc.cgroup.cpuset.cpus = 0
在主机和container之间共享文件夹
首先在container内部创建一个文件夹，比如说/mnt/share
$ mkdir /mnt/share
然后主机上也创建一个文件夹，比如说'/tmp/share'
$ mkdir /tmp/share
这个时候主机上保存container文件系统的目录下面也会产生/mnt/share这个目录，找到这个目录的绝对路径
修改container的配置文件config， 添加一行
lxc.mount.entry = /tmp/share /var/lib/lxc/centos_client/rootfs/mnt/share none bind 0 0
