你好,游客 登录 注册 搜索
背景:
阅读新闻

让Hadoop跑在云端系列文章 之 克隆虚拟机增加Hadoop节点

[日期:2015-01-21] 来源:粉丝日志  作者:粉丝日志 [字体: ]

让Hadoop跑在云端系列文章,介绍了如何整合虚拟化和Hadoop,让Hadoop集群跑在VPS虚拟主机上,通过云向用户提供存储和计算的服务。

现在硬件越来越便宜,一台非品牌服务器,2颗24核CPU,配48G内存,2T的硬盘,已经降到2万块人民币以下了。这种配置如果简单地放几个 web应用,显然是奢侈的浪费。就算是用来实现单节点的hadoop,对计算资源浪费也是非常高的。对于这么高性能的计算机,如何有效利用计算资源,就成 为成本控制的一项重要议题了。

通过虚拟化技术,我们可以将一台服务器,拆分成12台VPS,每台2核CPU,4G内存,40G硬盘,并且支持资源重新分配。多么伟大的技术啊!现在我们有了12个节点的hadoop集群, 让Hadoop跑在云端,让世界加速。

关于作者:

  • 张丹(Conan), 程序员Java,R,PHP,Javascript
  • weibo:@Conan_Z
  • blog: http://blog.fens.me
  • email: bsspirit@gmail.com

转载请注明出处:

http://blog.fens.me/hadoop-clone-node/

clone-guest

前言

通过虚拟化技术,我们可轻松的增加或删除一台虚拟机。像hadoop技术,安装,配置,运维,管理都很复杂,如果能通过虚拟化技术,降低运维成本, 是多么开心的一件事啊!设想一下,如果一个人能够管理1000个hadoop节点,那么小型公司也可以随随便便构建像百度,阿里一样的强大的计算集群环 境。世界也许会更奇妙!

当然,本文并不是讲一个人如何管理1000个hadoop节点。但我会介绍一种方式,通过克隆虚拟机来增加Hadoop节点。也许在大家的实践操作中,就能做出一个人运维1000个节点集群的方案。

目录 

  1. 系统环境介绍
  2. 克隆虚拟机
  3. 完成2个节点的hadoop集群

1. 系统环境介绍

我延续上篇文章的系统环境,让Hadoop跑在云端系列文章 之 创建Hadoop母体虚拟机

我们已成功地创建了Hadoop母体虚拟机c1。接下来,我们要用clone的方式创建c2,c3,c4,c5 ,4台克隆虚拟机。

2. 克隆虚拟机

在host中,打开虚拟机管理软件,查看c1的状态。


~ sudo virsh

virsh # list
 Id    Name                           State
----------------------------------------------------
 5     server3                        running
 6     server4                        running
 7     d2                             running
 8     r1                             running
 9     server2                        running
 18    server5                        running
 42    c1                             running

c1正在运行中,由于c2之前已经创建,我们已c3来举例说明。

创建克隆体c3


~ sudo virt-clone --connect qemu:///system -o c1 -n c3 -f /disk/sdb1/c3.img
ERROR    Domain with devices to clone must be paused or shutoff.

关闭c1,并重新克隆


virsh # destroy c1
Domain c1 destroyed

~ sudo virt-clone --connect qemu:///system -o c1 -n c3 -f /disk/sdb1/c3.img
ERROR    A disk path must be specified to clone '/dev/sdb5'

分区硬盘引入的错误。(无比强大的google,已经找不到对这个错误的解释了)

接下的操作:

  1. 重新启动c1,注释/etc/fstab自动挂载/dev/vdb1的操作(自行解决)
  2. 卸载给c1分配的分区硬盘/dev/sdb5

~ edit c1

<!-- 
<disk type='block' device='disk'>
<driver name='qemu' type='raw' cache='none'/>
<source dev='/dev/sdb5'/>
<target dev='vdb' bus='virtio'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x06' function='0x0'/>
</disk>
-->

再次创建克隆体c3


~ sudo virt-clone --connect qemu:///system -o c1 -n c3 -f /disk/sdb1/c3.img
Cloning c1.img                             1% [                               ]  47 MB/s | 426 MB     14:14 ETA
Cloning c1.img                                                                           |  40 GB     08:18

Clone 'c3' created successfully.

给克隆体c3挂载分区硬盘/dev/sdb7,并启动c3


virsh # edit c3

<disk type='block' device='disk'>
<driver name='qemu' type='raw' cache='none'/>
<source dev='/dev/sdb7'/>
<target dev='vdb' bus='virtio'/>
</disk>

virsh # start c3

virsh # console c3
Connected to domain c3
Escape character is ^]

Ubuntu 12.10 c1 ttyS0

c1 login: cos
Password:
Last login: Wed Jul 10 12:00:44 CST 2013 from 192.168.1.79 on pts/0
Welcome to Ubuntu 12.10 (GNU/Linux 3.5.0-32-generic x86_64)

 * Documentation:  https://help.ubuntu.com/
New release '13.04' available.
Run 'do-release-upgrade' to upgrade to it.

cos@c1:~$

对克隆体c3,有几个地方需要修改:

  1. hostname,hosts
  2. 静态IP
  3. DNS
  4. /dev/vdb1自动挂载
  5. 配置hadoop存储目录权限
  6. ssh自动验证
  7. hadoop的master,slave

1. hostname,hosts


~ sudo hostname c3
~ sudo vi /etc/hostname
c3

~ sudo vi /etc/hosts
127.0.1.1       c3

2. 静态IP


~ sudo vi /etc/network/interfaces
auto lo
iface lo inet loopback

# The primary network interface
auto eth0
#iface eth0 inet dhcp
iface eth0 inet static
address 192.168.1.32
netmask 255.255.255.0
gateway 192.168.1.1

改完IP后,我们重启一下,用ssh连接。


~ ssh cos@c3.wtmart.com

~ ifconfig
eth0      Link encap:Ethernet  HWaddr 52:54:00:06:b2:3a
          inet addr:192.168.1.32  Bcast:192.168.1.255  Mask:255.255.255.0
          inet6 addr: fe80::5054:ff:fe06:b23a/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:42 errors:0 dropped:0 overruns:0 frame:0
          TX packets:33 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:6084 (6.0 KB)  TX bytes:4641 (4.6 KB)

lo        Link encap:Local Loopback
          inet addr:127.0.0.1  Mask:255.0.0.0
          inet6 addr: ::1/128 Scope:Host
          UP LOOPBACK RUNNING  MTU:16436  Metric:1
          RX packets:34 errors:0 dropped:0 overruns:0 frame:0
          TX packets:34 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0
          RX bytes:2560 (2.5 KB)  TX bytes:2560 (2.5 KB)

3. DNS (内网的DNS)


~ sudo vi /etc/resolv.conf
nameserver 192.168.1.7

~ ping c1.wtmart.com
PING c1.wtmart.com (192.168.1.30) 56(84) bytes of data.
64 bytes from 192.168.1.30: icmp_req=1 ttl=64 time=0.485 ms
64 bytes from 192.168.1.30: icmp_req=2 ttl=64 time=0.552 ms

4. /dev/vdb1自动挂载


~ sudo mount /dev/vdb1 /home/cos/hadoop
~ sudo vi /etc/fstab
/dev/vdb1        /home/cos/hadoop      ext4    defaults 0       0

~ df -h
Filesystem              Size  Used Avail Use% Mounted on
/dev/mapper/u1210-root   36G  2.4G   32G   7% /
udev                    2.0G  4.0K  2.0G   1% /dev
tmpfs                   791M  224K  791M   1% /run
none                    5.0M     0  5.0M   0% /run/lock
none                    2.0G     0  2.0G   0% /run/shm
none                    100M     0  100M   0% /run/user
/dev/vda1               228M   29M  188M  14% /boot
/dev/vdb                148G  188M  140G   1% /home/cos/hadoop

5. 配置hadoop存储目录权限


~ sudo chown -R cos:cos hadoop/

~ mkdir /home/cos/hadoop/data
~ mkdir /home/cos/hadoop/tmp

~ sudo chmod 755 /home/cos/hadoop/data
~ sudo chmod 755 /home/cos/hadoop/tmp

6. ssh自动验证


~ rm -rf ~/.ssh/

~ ssh-keygen -t rsa
Generating public/private rsa key pair.
Enter file in which to save the key (/home/cos/.ssh/id_rsa):
Created directory '/home/cos/.ssh'.
Enter passphrase (empty for no passphrase):
Enter same passphrase again:
Your identification has been saved in /home/cos/.ssh/id_rsa.
Your public key has been saved in /home/cos/.ssh/id_rsa.pub.
The key fingerprint is:
54:1f:51:5f:5c:1d:ac:8a:9d:8f:fd:da:65:7e:f9:8d cos@c3
The key's randomart image is:
+--[ RSA 2048]----+
|          . oooo*|
|         . . . o+|
|        .   . . .|
|       .     .   |
|        S o o    |
|         . +     |
|            +   +|
|           . o.=+|
|             .Eo*|
+-----------------+
~ cat ~/.ssh/id_rsa.pub >> ~/.ssh/authorized_keys

~ cat ~/.ssh/authorized_keys
ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQCtIK3+hGeJQOigIN1ydDVpUzFeg/urnX2DaHhuv5ik8bGGDZWmSA+qPWAZQoZFBGqGMTshvMQeksjA2WiINbFpQCGuxSFx5a9Ad0XU8bGDFi+yYfKlp1ROZ+7Jz1+cO4tjrCX4Ncr3nZlddl6Uh/yMYU+iuRQ4Ga7GXgeYoSf7C5vQmzkYija0XNa8wFr0+aeD3hau6s8dWwsw7Dn/xVA3eMqK+4LDGH6dkn6tc6nVyNbzofXdtPOsCkwHpwozwuRBL37LYcmELe+oT/GifWf0Qp4rQD/9ObtHkhKrSW45bRH/WzvkyNxl04dKlIj26zIsh9zjMHF8o0ce+zjUl7aD cos@c3

7. hadoop的master,slave


~ cd /home/cos/toolkit/hadoop-1.0.3/conf
~  vi slaves
c1.wtmart.com
c3.wtmart.com

3. 完成2个节点的hadoop集群

重新启动c1节点,配置2个节点的hadoop集群


~ ssh cos@c1.wtmart.com
~ sudo mount /dev/vdb1 /home/cos/hadoop

配置slave


~ cd /home/cos/toolkit/hadoop-1.0.3/conf
~  vi slaves
c1.wtmart.com
c3.wtmart.com

DNS (内网的DNS)


~ sudo vi /etc/resolv.conf
nameserver 192.168.1.7

~  ping c3.wtmart.com
PING c3.wtmart.com (192.168.1.32) 56(84) bytes of data.
64 bytes from 192.168.1.32: icmp_req=1 ttl=64 time=0.673 ms
64 bytes from 192.168.1.32: icmp_req=2 ttl=64 time=0.429 ms

交换ssh公钥
复制c3的authorized_keys到c1的authorized_keys


~ scp cos@c3.wtmart.com:/home/cos/.ssh/authorized_keys .
~ cat authorized_keys >> /home/cos/.ssh/authorized_keys

~ cat /home/cos/.ssh/authorized_keys
ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQCuWCgfB8qSyEpKmUwnXvWtiCbzza1oD8oM3jm3EJzBRivEC/QV3k8v8zOHt2Cf4H6hYIvYHoSMilA2Wqbh1ny/70zcIYrwFiX5QvSjbEfsj7UmvxevxjB1/5F66TRLN/PyTiw3FmPYLkxvTP8CET02D2cgAN0n+XGTXQaaBqBElQGuiOJUAIvMUl0yg3mH7eP8TRlS4qYpllh04kirSbkOm6IYRDtGsrb90ew63l6F/MpPk/H6DVGC23PnD7ZcMr7VFyCkNPNqcEBwbL8qL1Hhnf7Lvlinp3M3zVU0Aet3TjkgwvcLPX8BWmrguVdBJJ3yqcocylh0YKN9WImAhVm7 cos@c1
ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQDU4sIHWxuyicIwFbRpDcoegDfSaUhmaBTSFSVTd/Uk8w0fTUcERNx9bZrtuiiPsOImvsBy9hN2Au/x36Jp4hO8DFxzqTNBcfD9xcEgOzHGqH7ZC5qMqx3Poy6DzN/rk9t/+wXyNCfR4kRhrPBNiF6gMDMTRQLpKK9VnY0nQ6FvOQ407gMAsyf0Fn31sHZJLtM4/kxsSOEsSNIk1V+gbIxJv2fJ/AON0/iW1zu7inUC/+YvEuTLClnUMzqFb/xKp25XxSV6a5YzThxs58KO5JCRq2Kk/SM0GSmCSkjKImUYDDjmi1P6wbrd4mh/4frQr1DqYyPeHE4UlHXD90agw767 cos@c3

把c1的authorized_keys,再分发给c3


~ scp /home/cos/.ssh/authorized_keys cos@c3.wtmart.com:/home/cos/.ssh/authorized_keys

从c1启动hadoop集群


~ start-all.sh

starting namenode, logging to /home/cos/toolkit/hadoop-1.0.3/libexec/../logs/hadoop-cos-namenode-c1.out
c1.wtmart.com: Warning: $HADOOP_HOME is deprecated.
c1.wtmart.com:
c1.wtmart.com: starting datanode, logging to /home/cos/toolkit/hadoop-1.0.3/libexec/../logs/hadoop-cos-datanode-c1.out
c3.wtmart.com: Warning: $HADOOP_HOME is deprecated.
c3.wtmart.com:
c3.wtmart.com: starting datanode, logging to /home/cos/toolkit/hadoop-1.0.3/libexec/../logs/hadoop-cos-datanode-c3.out
c1.wtmart.com: Warning: $HADOOP_HOME is deprecated.
c1.wtmart.com:
c1.wtmart.com: starting secondarynamenode, logging to /home/cos/toolkit/hadoop-1.0.3/libexec/../logs/hadoop-cos-secondarynamenode-c1.out
starting jobtracker, logging to /home/cos/toolkit/hadoop-1.0.3/libexec/../logs/hadoop-cos-jobtracker-c1.out
c3.wtmart.com: Warning: $HADOOP_HOME is deprecated.
c3.wtmart.com:
c3.wtmart.com: starting tasktracker, logging to /home/cos/toolkit/hadoop-1.0.3/libexec/../logs/hadoop-cos-tasktracker-c3.out
c1.wtmart.com: Warning: $HADOOP_HOME is deprecated.
c1.wtmart.com:
c1.wtmart.com: starting tasktracker, logging to /home/cos/toolkit/hadoop-1.0.3/libexec/../logs/hadoop-cos-tasktracker-c1.out

查看c1的进程


~ jps
8861 JobTracker
8486 NameNode
8750 SecondaryNameNode
9123 Jps
9001 TaskTracker
8612 DataNode

查看c3的进程


~ jps
3180 TaskTracker
3074 DataNode
3275 Jps

这样就建立起了,2个节点的hadoop集群。
上面是我们手动操作的过程比较复杂,接下来我们的任务就是写一个自动化的脚本完成上面的操作。

转载请注明出处:

http://blog.fens.me/hadoop-clone-node/





收藏 推荐 打印 | 录入:Cstor | 阅读:
本文评论   查看全部评论 (0)
表情: 表情 姓名: 字数
点评:
       
评论声明
  • 尊重网上道德,遵守中华人民共和国的各项有关法律法规
  • 承担一切因您的行为而直接或间接导致的民事或刑事法律责任
  • 本站管理人员有权保留或删除其管辖留言中的任意内容
  • 本站有权在网站内转载或引用您的评论
  • 参与本评论即表明您已经阅读并接受上述条款