玩轉docker-簡單例項
主要是想通過一個例項來說明docker的最顯著的特徵:資料隔離,順便帶領大家熟悉一下docker的基本命令用法,揭開其神祕的面紗,讓大家也能領略到,當今網際網路大資料行業,最火的虛擬化技術,也不過如此,哈哈!
建立mysql5.6容器 1master+3個slave
docker run --name mysql-master -d -P hub.c.163.com/nce2/mysql:5.6
docker run --name mysql-slave1 -d -P hub.c.163.com/nce2/mysql:5.6
驗證容器狀態
[root@bogon ~]# docker ps CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES 907bbbf25d25 hub.c.163.com/nce2/mysql:5.6 "/run.sh" 5 minutes ago Up 5 minutes 3306/tcp mysql-slave3 a81df6c86808 hub.c.163.com/nce2/mysql:5.6 "/run.sh" 5 minutes ago Up 5 minutes 3306/tcp mysql-slave2 375eabd4c598 hub.c.163.com/nce2/mysql:5.6 "/run.sh" 5 minutes ago Up 5 minutes 3306/tcp mysql-slave1 1651d1cab219 hub.c.163.com/nce2/mysql:5.6 "/run.sh" 14 minutes ago Up 14 minutes 3306/tcp mysql-master
通過主機命令列進入master容器
docker exec -it mysql-master bash
[root@bogon ~]# docker exec -it mysql-master bash
root@1651d1cab219:/#
在master中建立一個數據庫test_docker
root@1651d1cab219:/# mysql -uroot -p Enter password: Welcome to the MySQL monitor. Commands end with ; or \g. Your MySQL connection id is 4 Server version: 5.6.19-v1-log MySQL Community Server (GPL) Copyright (c) 2000, 2014, Oracle and/or its affiliates. All rights reserved. Oracle is a registered trademark of Oracle Corporation and/or its affiliates. Other names may be trademarks of their respective owners. Type 'help;' or '\h' for help. Type '\c' to clear the current input statement. mysql> show databases; +--------------------+ | Database | +--------------------+ | information_schema | | #bak_database | | mysql | | performance_schema | | test | +--------------------+ 5 rows in set (0.02 sec) mysql> create database test_docker; Query OK, 1 row affected (0.06 sec) mysql> show databases; +--------------------+ | Database | +--------------------+ | information_schema | | #bak_database | | mysql | | performance_schema | | test | | test_docker | +--------------------+ 6 rows in set (0.00 sec)
在slave1中建立一個數據庫test_docker
[root@bogon ~]# docker exec -it mysql-slave bash
Error response from daemon: No such container: mysql-slave
[root@bogon ~]# docker exec -it mysql-slave1 bash
root@375eabd4c598:/# mysql -uroot -p
Enter password:
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 4
Server version: 5.6.19-v1-log MySQL Community Server (GPL)
Copyright (c) 2000, 2014, Oracle and/or its affiliates. All rights reserved.
Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
mysql> show databases;
+--------------------+
| Database |
+--------------------+
| information_schema |
| #bak_database |
| mysql |
| performance_schema |
| test |
+--------------------+
5 rows in set (0.00 sec)
通過以上的資訊說明master與slave是資料隔離的,
所以我們可以通過docker建立N個mysql容器,
然後就能以很小的代價就能學習《高可用MySQL》中的資料模型 再也不用發愁機器不夠用。
後續操作
登入到master容器
[root@bogon ~]# docker exec -it mysql-master bash
root@1651d1cab219:/#
怎麼檢視容器的作業系統環境
一般就是
uname -a
cat /etc/pro
cat /etc/lsb-release
很幸運我們的容器是ubuntu14.04
root@1651d1cab219:/# cat /etc/lsb-release
DISTRIB_ID=Ubuntu
DISTRIB_RELEASE=14.04
DISTRIB_CODENAME=trusty
DISTRIB_DESCRIPTION="Ubuntu 14.04.3 LTS"
但是執行 apt-get install時候卻什麼也裝不了
需要更改
cd /etc/apt/
沒有 vi vim ee 編輯器 只好追加內容到 sources.list
echo deb http://mirrors.163.com/ubuntu/ trusty main restricted universe multiverse >> sources.list
echo deb http://mirrors.163.com/ubuntu/ trusty-security main restricted universe multiverse >> sources.list
echo deb http://mirrors.163.com/ubuntu/ trusty-updates main restricted universe multiverse >> sources.list
echo deb http://mirrors.163.com/ubuntu/ trusty-proposed main restricted universe multiverse >> sources.list
echo deb http://mirrors.163.com/ubuntu/ trusty-backports main restricted universe multiverse >> sources.list
echo deb-src http://mirrors.163.com/ubuntu/ trusty main restricted universe multiverse >> sources.list
echo deb-src http://mirrors.163.com/ubuntu/ trusty-security main restricted universe multiverse >> sources.list
echo deb-src http://mirrors.163.com/ubuntu/ trusty-updates main restricted universe multiverse >> sources.list
echo deb-src http://mirrors.163.com/ubuntu/ trusty-proposed main restricted universe multiverse >> sources.list
echo deb-src http://mirrors.163.com/ubuntu/ trusty-backports main restricted universe multiverse >> sources.list
然後 更新源
apt-get update
apt-get install vim
然後通過vim把sources.list檔案的前兩行刪除掉 再重新update一下。
apt-get update
安裝一個網路工具獲取ip
apt-get install net-tools
獲取到master的ip地址
root@1651d1cab219:/# ifconfig
eth0 Link encap:Ethernet HWaddr 02:42:ac:11:00:02
inet addr:172.17.0.2 Bcast:0.0.0.0 Mask:255.255.0.0
inet6 addr: fe80::42:acff:fe11:2/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:15119 errors:0 dropped:0 overruns:0 frame:0
TX packets:12633 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:34197557 (34.1 MB) TX bytes:897732 (897.7 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:65536 Metric:1
RX packets:22 errors:0 dropped:0 overruns:0 frame:0
TX packets:22 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:2212 (2.2 KB) TX bytes:2212 (2.2 KB)
slave也需要這麼做
還有一種方法
可以建立Dockerfile依賴mysql映象建立一個新的映象。
上訴命令通過RUN來執行建立的新容器會有安裝的軟體。
最後通過slave的docker連線到master的容器mysql伺服器上
master的伺服器mysql賬號root賦值許可權
mysql> grant all privileges on *.* to root@'%' identified by '';
Query OK, 0 rows affected (0.02 sec)
mysql> flush privileges;
Query OK, 0 rows affected (0.02 sec)
slave伺服器執行如下命令
[root@bogon ~]# mysql -uroot -p -h 172.17.0.2
Enter password:
Welcome to the MariaDB monitor. Commands end with ; or \g.
Your MySQL connection id is 6
Server version: 5.6.19-v1-log MySQL Community Server (GPL)
Copyright (c) 2000, 2016, Oracle, MariaDB Corporation Ab and others.
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
MySQL [(none)]>
在master上將test_docker資料庫刪除,看slave的終端是否也不顯示已刪除的庫
master操作
mysql> show databases;
+--------------------+
| Database |
+--------------------+
| information_schema |
| #bak_database |
| mysql |
| performance_schema |
| test |
| test_docker |
+--------------------+
6 rows in set (0.00 sec)
mysql> drop database test_docker;
Query OK, 0 rows affected (0.06 sec)
mysql> show databases;
+--------------------+
| Database |
+--------------------+
| information_schema |
| #bak_database |
| mysql |
| performance_schema |
| test |
+--------------------+
5 rows in set (0.00 sec)
slave操作
小插曲:
在初次建立docker mysql容器例項的時候,中間報了一個如下錯誤:
不管如何啟動mysql-master 或者 mysql-slave 例項,總是出現上述異常,後來,問了一下度娘,終於找到了解決方法,原來是因為doker 的 RPM packages需要升級了, 最後打通了此條探索的道路,甚是不容易哈,解決方法,現共享如下:
yum downgrade docker docker-client docker-common
上述是本節的主要內容,現分享給各位小夥伴們,歡迎各位能提出寶貴的意見或者建議,在成為土豪路上一起成長!
完