= LXC - Linux Containers =

[[PageOutline]]

== 2014-01-11 ==

 * <參考> [http://ofirm.wordpress.com/2014/01/05/creating-a-virtualized-fully-distributed-hadoop-cluster-using-linux-containers/ Creating a virtualized fully-distributed Hadoop cluster using Linux Containers]
 * 測試環境：Debian Wheezy 7.1 netinstall ISO with [http://github.com/jazzwang/preseed preseed]
{{{
jazz@debian:~$ lsb_release -a
No LSB modules are available.
Distributor ID:	Debian
Description:	Debian GNU/Linux 7.3 (wheezy)
Release:	7.3
Codename:	wheezy
}}}
 * 安裝 LXC
{{{
jazz@debian:~$ sudo apt-get install lxc
}}}
 * 產生虛擬機器
{{{
jazz@debian:~$ sudo lxc-create -t debian -n test1
jazz@debian:~$ sudo lxc-start -d -n test1
}}}
 * 安裝 LXC Web Panel
{{{
root@debian:~# wget http://lxc-webpanel.github.io/tools/install.sh -O - | bash
}}}
 * <狀況> 指令可以建立 LXC VM, 但網頁似乎不太靈光。

== 2014-01-12 ==

 * 測試環境：Ubuntu 12.04 LTS
{{{
jazz@jazzbook:~$ lsb_release -a
No LSB modules are available.
Distributor ID:	Ubuntu
Description:	Ubuntu 12.04.2 LTS
Release:	12.04
Codename:	precise
}}}
 * 感覺上 LXC 1.0 的功能比較齊全(Ex. 支援根據 DNS 分配 IP 的機制)，因此直接採用 precise-backports 套件庫中的 lxc 1.0 版本
{{{
echo "deb http://free.nchc.org.tw/ubuntu precise-backports main universe" > /tmp/precise-backport.list
sudo mv /tmp/precise-backport.list /etc/apt/sources.list.d/
sudo apt-get update
}}}
 * 安裝 LXC 1.0 版本
{{{
sudo apt-get install lxc
}}}
{{{
jazz@jazzbook:~$ lxc-version 
lxc version: 1.0.0.alpha1
}}}
 * 根據 /etc/default/lxc-net 的說明，可以設定一個檔案，來根據 hostname 決定 IP 分配
{{{
#!sh
# Uncomment the next line if you'd like to use a conf-file for the lxcbr0
# dnsmasq.  For instance, you can use 'dhcp-host=mail1,10.0.3.100' to have
# container 'mail1' always get ip address 10.0.3.100.
#LXC_DHCP_CONFILE=/etc/lxc/dnsmasq.conf
}}}
{{{
jazz@jazzbook:~$ sudo su -
root@jazzbook:~# echo "LXC_DHCP_CONFILE=/etc/lxc/dnsmasq.conf" >> /etc/default/lxc-net
root@jazzbook:~# cat > /etc/lxc/dnsmasq.conf << EOF
dhcp-host=hdp11,10.0.1.111
dhcp-host=hdp12,10.0.1.112
dhcp-host=hdp13,10.0.1.113
dhcp-host=hdp14,10.0.1.114
dhcp-host=hdp15,10.0.1.115
dhcp-host=hdp16,10.0.1.116
dhcp-host=hdp17,10.0.1.117
dhcp-host=hdp18,10.0.1.118
dhcp-host=hdp19,10.0.1.119
dhcp-host=hdp20,10.0.1.120
dhcp-host=hdp21,10.0.1.121
dhcp-host=hdp22,10.0.1.122
dhcp-host=hdp23,10.0.1.123
dhcp-host=hdp24,10.0.1.124
dhcp-host=hdp25,10.0.1.125
dhcp-host=hdp26,10.0.1.126
dhcp-host=hdp27,10.0.1.127
dhcp-host=hdp28,10.0.1.128
dhcp-host=hdp29,10.0.1.129
dhcp-host=hdp30,10.0.1.130
EOF
}}}
 * 建立 20 個 VM 的主機名稱對應(hostname)
{{{
root@jazzbook:~# cat >> /etc/hosts << EOF
# for LXC
10.0.1.111	hdp11
10.0.1.112      hdp12
10.0.1.113      hdp13
10.0.1.114      hdp14
10.0.1.115      hdp15
10.0.1.116      hdp16
10.0.1.117      hdp17
10.0.1.118      hdp18
10.0.1.119      hdp19
10.0.1.120      hdp20
10.0.1.121      hdp21
10.0.1.122      hdp22
10.0.1.123      hdp23
10.0.1.124      hdp24
10.0.1.125      hdp25
10.0.1.126      hdp26
10.0.1.127      hdp27
10.0.1.128      hdp28
10.0.1.129      hdp29
10.0.1.130      hdp30
EOF
}}}
 * 為了讓根據 DNS 主機名稱對應分配 IP 的機制生效，必須重新啟動 lxc-net
{{{
root@jazzbook:~# /etc/init.d/lxc restart
root@jazzbook:~# /etc/init.d/lxc-net restart
}}}
 * 先建立五個 LXC VM 試試看
{{{
root@jazzbook:~# for ((i=11;i<=15;i++)); do lxc-create -t ubuntu -n hdp$i; done

Checking cache download in /var/cache/lxc/precise/rootfs-i386 ... 
Copy /var/cache/lxc/precise/rootfs-i386 to /usr/lib/i386-linux-gnu/lxc ... 
Copying rootfs to /usr/lib/i386-linux-gnu/lxc ...
/bin/bash: warning: setlocale: LC_ALL: cannot change locale (en_US.UTF-8)
Generating locales...
  en_US.UTF-8... done
Generation complete.
Creating SSH2 RSA key; this may take some time ...
Creating SSH2 DSA key; this may take some time ...
Creating SSH2 ECDSA key; this may take some time ...

##
# The default user is 'ubuntu' with password 'ubuntu'!
# Use the 'sudo' command to run tasks as root in the container.
##
}}}
 * 從以上訊息可以得知，預設的帳號密碼都是 ubuntu
 * 啟動 5 個 LXC VM
{{{
root@jazzbook:~# for ((i=11;i<=15;i++)); do lxc-start -d -n hdp$i; done
}}}
 * 用 lxc-ls 查詢分配到的 IP 位置，看樣子 LXC_DHCP_CONFILE 的設定沒啥用 :P
{{{
root@jazzbook:~# lxc-ls --fancy
NAME   STATE    IPV4        IPV6  AUTOSTART  
-------------------------------------------
hdp11  RUNNING  10.0.3.232  -     NO         
hdp12  RUNNING  10.0.3.119  -     NO         
hdp13  RUNNING  10.0.3.201  -     NO         
hdp14  RUNNING  10.0.3.210  -     NO         
hdp15  RUNNING  10.0.3.243  -     NO       
}}}
 * 看樣子跟 /var/lib/misc/dnsmasq.lxcbr0.leases 有關，因此清除該檔案，再重來一次
{{{
service lxc-net stop
rm /var/lib/misc/dnsmasq.lxcbr0.leases 
service lxc-net start
}}}
{{{
root@jazzbook:~# for ((i=11;i<=15;i++)); do lxc-stop -n hdp$i; done
root@jazzbook:~# for ((i=11;i<=15;i++)); do lxc-destroy -n hdp$i; done
root@jazzbook:~# for ((i=11;i<=15;i++)); do lxc-create -t ubuntu -n hdp$i; done
root@jazzbook:~# for ((i=11;i<=15;i++)); do lxc-start -d -n hdp$i; done
}}}
 * <結果> 一樣還是沒有照 hostname 分配 IP ..... XD
{{{
root@jazzbook:~# lxc-ls --fancy
NAME   STATE    IPV4        IPV6  AUTOSTART  
-------------------------------------------
hdp11  RUNNING  10.0.3.238  -     NO         
hdp12  RUNNING  10.0.3.36   -     NO         
hdp13  RUNNING  10.0.3.72   -     NO         
hdp14  RUNNING  10.0.3.214  -     NO         
hdp15  RUNNING  10.0.3.9    -     NO   
}}}
 * 安裝 LXC Web Panel
{{{
root@jazzbook:~# wget http://lxc-webpanel.github.io/tools/install.sh -O - | bash
}}}
=== LXC PXE Boot ? ===

 * <問題> LXC 可以支援 PXE 開機嘛？