一、建立一个10G分区,并格式为ext4文件系统;node
(1) 要求其block大小为2048, 预留空间百分比为2, 卷标为MYDATA, 默认挂载属性包含acl;linux
# 建立10G分区 [root@CentOS7 ~]# fdisk /dev/sdb 命令(输入 m 获取帮助):n Partition type: p primary (0 primary, 0 extended, 4 free) e extended Select (default p): p 分区号 (1-4,默认 1):1 起始 扇区 (2048-104857599,默认为 2048): 将使用默认值 2048 Last 扇区, +扇区 or +size{K,M,G} (2048-104857599,默认为 104857599):+10G 分区 1 已设置为 Linux 类型,大小设为 10 GiB 命令(输入 m 获取帮助):p 磁盘 /dev/sdb:53.7 GB, 53687091200 字节,104857600 个扇区 Units = 扇区 of 1 * 512 = 512 bytes 扇区大小(逻辑/物理):512 字节 / 512 字节 I/O 大小(最小/最佳):512 字节 / 512 字节 磁盘标签类型:dos 磁盘标识符:0xbde73b0a 设备 Boot Start End Blocks Id System /dev/sdb1 2048 20973567 10485760 83 Linux 命令(输入 m 获取帮助):w The partition table has been altered! Calling ioctl() to r
# 设置文件系统类型并指定参数设置 [root@CentOS7 ~]# mke2fs -t ext4 -b 2048 -m 2 -L 'MYDATA' /dev/sdb1 mke2fs 1.42.9 (28-Dec-2013) 文件系统标签=MYDATA OS type: Linux 块大小=2048 (log=1) 分块大小=2048 (log=1) Stride=0 blocks, Stripe width=0 blocks 655360 inodes, 5242880 blocks 104857 blocks (2.00%) reserved for the super user 第一个数据块=0 Maximum filesystem blocks=273678336 320 block groups 16384 blocks per group, 16384 fragments per group 2048 inodes per group Superblock backups stored on blocks: 16384, 49152, 81920, 114688, 147456, 409600, 442368, 802816, 1327104, 2048000, 3981312 Allocating group tables: 完成 正在写入inode表: 完成 Creating journal (32768 blocks): 完成 Writing superblocks and filesystem accounting information: 完成 # 设置文件系统的默认挂载属性包含acl [root@CentOS7 ~]# tune2fs -o acl /dev/sdb1 tune2fs 1.42.9 (28-Dec-2013)
(2) 挂载至/data/mydata目录,要求挂载时禁止程序自动运行,且不更新文件的访问时间戳;git
# 建立挂载文件夹 [root@CentOS7 ~]# mkdir -pv /data/mydata mkdir: 已建立目录 "/data" mkdir: 已建立目录 "/data/mydata" [root@CentOS7 ~]# mount -o noexec,noatime /dev/sdb1 /data/mydata [root@CentOS7 ~]# mount /dev/sdb1 on /data/mydata type ext4 (rw,noexec,noatime,seclabel,data=ordered)
mount -o options:(挂载文件系统的选项) async:异步模式; sync:同步模式; atime/noatime:是否更新访问时间戳,包含目录和文件; diratime/nodiratime:是否更新目录的访问时间戳 auto/noauto:是否支持自动挂载 exec/noexec:是否支持应用程序自动运行 dev/nodev:是否支持在此文件系统上使用设备文件; remount:从新挂载 user/nouser:是否容许普通用户挂载此设备 acl:启用此文件系统上的acl功能 注意:上述选项可多个同时使用,彼此使用逗号分隔;
二、建立一个大小为1G的swap分区,并建立好文件系统,并启用之;shell
[root@CentOS7 ~]# fdisk /dev/sdb 命令(输入 m 获取帮助):n Partition type: p primary (1 primary, 0 extended, 3 free) e extended Select (default p): p 分区号 (2-4,默认 2):2 起始 扇区 (20973568-104857599,默认为 20973568): 将使用默认值 20973568 Last 扇区, +扇区 or +size{K,M,G} (20973568-104857599,默认为 104857599):+1G 分区 2 已设置为 Linux 类型,大小设为 1 GiB 命令(输入 m 获取帮助):t 分区号 (1,2,默认 2):2 Hex 代码(输入 L 列出全部代码):82 已将分区“Linux”的类型更改成“Linux swap / Solaris” 命令(输入 m 获取帮助):p 磁盘 /dev/sdb:53.7 GB, 53687091200 字节,104857600 个扇区 Units = 扇区 of 1 * 512 = 512 bytes 扇区大小(逻辑/物理):512 字节 / 512 字节 I/O 大小(最小/最佳):512 字节 / 512 字节 磁盘标签类型:dos 磁盘标识符:0xbde73b0a 设备 Boot Start End Blocks Id System /dev/sdb1 2048 20973567 10485760 83 Linux /dev/sdb2 20973568 23070719 1048576 82 Linux swap / Solaris 命令(输入 m 获取帮助):w [root@CentOS7 ~]# partx -a /dev/sdb partx: /dev/sdb: error adding partition 1 [root@CentOS7 ~]# mkswap /dev/sdb2 正在设置交换空间版本 1,大小 = 1048572 KiB 无标签,UUID=b30e0963-f82f-4a2f-8fb4-5f763d5f78bd [root@CentOS7 ~]# free -m total used free shared buff/cache available Mem: 481 122 211 4 146 312 Swap: 1023 0 1023
三、写一个脚本vim
(1)、获取并列出当前系统上的全部磁盘设备;centos
(2)、显示每一个磁盘设备上每一个分区相关的空间使用信息;安全
[root@mylinux tmp]# vim diskinfo.sh
#!/bin/bash # 获取并列出当前系统上的全部磁盘设备 echo "$(fdisk -l /dev/[sh]d[a-z] | grep -o '^Disk /dev/[sh]d[a-z]')" # 显示分区空间使用信息: diskDev=$(fdisk -l /dev/[sh]d[a-z] | grep -o '^/dev/[sh]d[a-z][[:digit:]]') for i in $diskDev do echo "$(df -lh $i)\n" done
[root@mylinux tmp]# chmod +x diskinfo.sh [root@mylinux tmp]# ./diskinfo.sh Disk /dev/sda Disk /dev/sdb Disk /dev/sdc Disk /dev/sdd Disk /dev/sde Filesystem Size Used Avail Use% Mounted on /dev/sda1 297M 158M 140M 54% /boot\n Filesystem Size Used Avail Use% Mounted on devtmpfs 479M 0 479M 0% /dev\n Filesystem Size Used Avail Use% Mounted on devtmpfs 479M 0 479M 0% /dev\n Filesystem Size Used Avail Use% Mounted on devtmpfs 479M 0 479M 0% /dev\n Filesystem Size Used Avail Use% Mounted on devtmpfs 479M 0 479M 0% /dev\n
四、总结RAID的各个级别及其组合方式和性能的不一样;bash
RAID 0:将多个磁盘并列起来,成为一个大硬盘。存放数据时,其将数据分段同时写入,速度快。app
优势:并行I/O,读写速度最快。dom
缺点:不具备冗余功能,有一个硬盘坏,则数据所有丢失。
最少磁盘数:2
RAID 1:两组相同的磁盘系统互做镜像,在主硬盘上存放数据的同时也在镜像硬盘上写相同的数据。
当主硬盘(物理)损坏时,镜像硬盘则代替主硬盘的工做,至关于备份。
优势:容许单个磁盘出错,可靠性最高,数据安全性在全部的RAID级别上来讲是最好的。
缺点:速度没有提升,其磁盘的利用率却只有50%,是全部RAID上磁盘利用率最低的一个级别。
最少磁盘数:2
RAID 3:以一个硬盘来存放数据的奇偶校验位,数据则分段存储于其他硬盘中。
像RAID0同样以并行的方式来存放数据,但因为每次存放都须要进行校验,速度没有RAID0快。
校验盘固定为其中一块硬盘。
优势:写入性能最好,容许单个磁盘出错,可靠性高,且磁盘利用率高(可用空间为n-1)
缺点:没有多任务,做为存放校验位的硬盘,工做负荷会很大,由于每次写操做,都会把生成的校验信息写入该磁盘,而其它磁盘的负荷相对较小,这会对性能有必定的影响
最少磁盘数:3
RAID 4:跟Raid3相同,区别在于Raid3只能单任务,Raid4 具有多任务及容错功能 Parity 磁盘驱动器形成性能瓶颈
RAID 5:在RAID 3的基础上,进行一些改进,奇偶校验数据均匀存放在阵列中的各个盘上,
优势:容许单个磁盘出错,可靠性高,相对Raid3来讲,硬盘负荷相对较小。
缺点:每次存放数据会进行奇偶校验,增长工做负荷。损失一块硬盘空间。
最少磁盘数:3
RAID 6:相似于RAID 5,但其奇偶校验盘为2个,均匀存放在阵列中的各个盘上。
优势:容许2块磁盘出错,可靠性比RAID更高
缺点:存放数据时增长工做负荷,空间利用率低,为n-2
最少磁盘数:4
RAID-10:先将硬盘两两一组作成RAID-1,而后再将这一组组的RAID-1作成RAID-0。
优势:读、写性能提高,容许同一组内1个硬盘损坏
缺点:可用空间50%
最少磁盘数:4
RAID-01:先将硬盘分为2组,每一组硬盘单独作成RAID-0,而后将这两组硬盘作成RAID-1。
优势:读、写性能提高,有容错能力,能够损坏任意一组的硬盘(能够一组全坏)
缺点:可用空间50%
最少磁盘数:4
五、建立一个大小为10G的RAID1,要求有一个空闲盘,并且CHUNK大小为128k;
#对硬盘sde分配3个分区,大小均为10G,设置分区类型为fd(Linux raid auto) [root@mylinux ~]# fdisk /dev/sde Command (m for help): n Partition type: p primary (0 primary, 0 extended, 4 free) e extended Select (default p): p Partition number (1-4, default 1): First sector (2048-125829119, default 2048): Using default value 2048 Last sector, +sectors or +size{K,M,G} (2048-125829119, default 125829119): +10G Partition 1 of type Linux and of size 10 GiB is set Command (m for help): n Partition type: p primary (1 primary, 0 extended, 3 free) e extended Select (default p): p Partition number (2-4, default 2): First sector (20973568-125829119, default 20973568): Using default value 20973568 Last sector, +sectors or +size{K,M,G} (20973568-125829119, default 125829119): +10G Partition 2 of type Linux and of size 10 GiB is set Command (m for help): n Partition type: p primary (2 primary, 0 extended, 2 free) e extended Select (default p): p Partition number (3,4, default 3): 3 First sector (41945088-125829119, default 41945088): Using default value 41945088 Last sector, +sectors or +size{K,M,G} (41945088-125829119, default 125829119): +10G Partition 3 of type Linux and of size 10 GiB is set Command (m for help): t Partition number (1-3, default 3): 1 Hex code (type L to list all codes): fd Changed type of partition 'Linux' to 'Linux raid autodetect' Command (m for help): t Partition number (1-3, default 3): 2 Hex code (type L to list all codes): fd Changed type of partition 'Linux' to 'Linux raid autodetect' Command (m for help): t Partition number (1-3, default 3): 3 Hex code (type L to list all codes): fd Changed type of partition 'Linux' to 'Linux raid autodetect' Command (m for help): p Disk /dev/sde: 64.4 GB, 64424509440 bytes, 125829120 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk label type: dos Disk identifier: 0x1646a2bb Device Boot Start End Blocks Id System /dev/sde1 2048 20973567 10485760 fd Linux raid autodetect /dev/sde2 20973568 41945087 10485760 fd Linux raid autodetect /dev/sde3 41945088 62916607 10485760 fd Linux raid autodetect [root@mylinux ~]# partx -a /dev/sde partx: /dev/sde: error adding partitions 1-2
[root@mylinux ~]# yum install mdadm #个别须要使用yum安装mdadm软件包 # 使用mdadm命令建立软raid [root@mylinux ~]# mdadm -C /dev/md0 -a yes -l 1 -n 2 -x 1 -c 128 /dev/sde{1..3} mdadm: Note: this array has metadata at the start and may not be suitable as a boot device. If you plan to store '/boot' on this device please ensure that your boot-loader understands md/v1.x metadata, or use --metadata=0.90 Continue creating array? y mdadm: Defaulting to version 1.2 metadata mdadm: array /dev/md0 started.
PS:语法格式:mdadm [mode] <raiddevice> [options] <component-devices> 建立:-C -n #: 使用#个块设备来建立此RAID; -l #:指明要建立的RAID的级别,mdadm支持的RAID级别:LINEAR, RAID0, RAID1, RAID4, RAID5, RAID6, RAID10; -a {yes|no}:自动建立目标RAID设备的设备文件; -c CHUNK_SIZE: 指明块大小; -x #: 指明空闲盘的个数。 装配: -A 监控: -F 管理: -f:将磁盘人工标记为损坏(faulty) -r:将块设备从RAID卷中移除 -a:向RAID卷中添加块设备 -S, --stop:拆除RAID卷,释放全部块设备
# 验证结果:可以使用mdadm -D 或 cat /proc/mdstat [root@localhost tmp]# mdadm -D /dev/md0
六、建立一个大小为4G的RAID5设备,chunk大小为256k,格式化ext4文件系统,要求可开机自动挂载至/backup目录,并且不更新访问时间戳,且支持acl功能;
# 实验环境搭建,新建三个2GB大小的分区,以下sde{5,6,7},并设置分区格式为fd [root@localhost tmp]# fdisk /dev/sde Device Boot Start End Blocks Id System /dev/sde1 2048 20973567 10485760 fd Linux raid autodetect /dev/sde2 20973568 41945087 10485760 fd Linux raid autodetect /dev/sde3 41945088 62916607 10485760 fd Linux raid autodetect /dev/sde4 62916608 104859647 20971520 5 Extended /dev/sde5 62918656 67112959 2097152 fd Linux raid autodetect /dev/sde6 67115008 71309311 2097152 fd Linux raid autodetect /dev/sde7 71311360 75505663 2097152 fd Linux raid autodetect
[root@localhost tmp]# mdadm -C /dev/md1 -a yes -l 5 -n 3 -c 256 /dev/sde{5,6,7} mdadm: Defaulting to version 1.2 metadata mdadm: array /dev/md1 started. [root@localhost tmp]# mke2fs -t ext4 -L 'MD1' /dev/md1 mke2fs 1.42.9 (28-Dec-2013) Filesystem label=MD1 OS type: Linux Block size=4096 (log=2) Fragment size=4096 (log=2) Stride=64 blocks, Stripe width=128 blocks 262144 inodes, 1047552 blocks 52377 blocks (5.00%) reserved for the super user First data block=0 Maximum filesystem blocks=1073741824 32 block groups 32768 blocks per group, 32768 fragments per group 8192 inodes per group Superblock backups stored on blocks: 32768, 98304, 163840, 229376, 294912, 819200, 884736 Allocating group tables: done Writing inode tables: done Creating journal (16384 blocks): done Writing superblocks and filesystem accounting information: done [root@localhost ~]# mkdir /backup #建立挂载目录 [root@localhost ~]# vim /etc/fstab #修改配置文件设置开机自动挂载,在文件最后面添加如下内容。 /dev/md1 /backup ext4 noatime,acl 0 0 # 挂载使用-a [root@localhost ~]# mount -a [root@localhost ~]# mount #查看已挂载状况 ...(中间省略)... /dev/md1 on /backup type ext4 (rw,noatime,seclabel,stripe=128,data=ordered)
七、写一个脚本
(1) 接受一个以上文件路径做为参数;
(2) 显示每一个文件拥有的行数;
(3) 总结说明本次共为几个文件统计了其行数;
[root@localhost bin]# vim sumfile.sh #!/bin/bash # declare -i sumfile=0 if [ $# -lt 1 ];then echo "Error: Please enter at least one path." exit 1 fi for i in $@; do if [ -f $i ];then echo "Filename:$i lines:`wc -l $i | cut -d" " -f1` " let sumfile++ else echo "Error: $i is not a correct file path." fi done echo "Total files count is: $sumfile"
# 命令执行 [root@localhost bin]# bash -n sumfile.sh # 测试命令是否存在语法错误 [root@localhost bin]# bash sumfile.sh /etc/passwd /etc/fstab Filename:/etc/passwd lines:33 Filename:/etc/fstab lines:12 Total files count is: 2 # 错误测试: [root@localhost bin]# bash sumfile.sh # 不输入文件路径做为参数时候 Error: Please enter at least one path. [root@localhost bin]# bash sumfile.sh /etc/passwd /etc/ # 其中一个参数不是文件,而是文件夹时 Filename:/etc/passwd lines:33 Error: /etc/ is not a correct file path. Total files count is: 1
八、写一个脚本
(1) 传递两个以上字符串看成用户名;
(2) 建立这些用户;且密码同用户名;
(3) 总结说明共建立了几个用户;
[root@localhost bin]# vim adduser2.sh #!/bin/bash # declare usercount=0 if [ $# -lt 2 ];then echo "Error: Please enter two or more usernames." exit 1 fi for i in $@; do id $i &> /dev/null if [ $? -eq 0 ] then echo "$i is already exist" else useradd $i echo "$i" | passwd --stdin $i &> /dev/null let usercount++ echo "username: $i add finished. " fi done echo "Total add user counts is $usercount"
# 脚本执行 [root@localhost bin]# bash adduser2.sh terry1 terry2 terry3 username: terry1 add finished. username: terry2 add finished. username: terry3 add finished. Total add user counts is 3 # 错误演示 [root@localhost bin]# bash adduser2.sh Error: Please enter two or more usernames. [root@localhost bin]# bash adduser2.sh terry1 te terry1 is already exist username: te add finished. Total add user counts is 1
九、写一个脚本,新建20个用户,visitor1-visitor20;计算他们的ID之和;
# 新建20个用户并计算他们ID总和的shell脚本: [root@localhost bin]# vim sumid.sh #!/bin/bash # declare -i sumid=0 if [ ! $UID -eq 0 ]; then echo "Only root have permission to do these." exit 1 fi for i in {1..20}; do if id visitor$i &> /dev/null; then echo "visitor$i exists." else useradd visitor$i if [ $? -eq 0 ]; then echo "visitor$i" | passwd --stdin visitor$i &> /dev/null echo "Add visitor$i finished." fi fi ids=$(id -u visitor$i) let sumid+=ids done echo "UID sum is:$sumid"
# 上述shell脚本中统计ID总和的两条计算命令要放在if条件外,这样能够避免因个别用户ID已经建立致使统计结果不许确。
[root@localhost bin]# bash sumid.sh Add visitor1 finished. ...(中间省略)... Add visitor20 finished. UID sum is:20490
# 删除用户脚本:由于上述脚本测试过程当中执行屡次,有部分用户已经建立好了,为了更好地测试,写个脚本删除 [root@localhost bin]# vim deluser.sh #!/bin/bash # for i in {1..20}; do name=visitor userdel -rf $name$i echo "User: $name$i had been delete completed." done [root@localhost bin]# bash -n deluser.sh [root@localhost bin]# bash deluser.sh User: visitor1 had been delete completed. ...(中间省略)... User: visitor20 had been delete completed.
十、写一脚本,分别统计/etc/rc.d/rc.sysinit、/etc/rc.d/init.d/functions和/etc/fstab文件中以#号开头的行数之和,以及总的空白行数;
[root@localhost bin]# vim sum1.sh #!/bin/bash # declare -i sum1=0 declare -i sum2=0 for file in {/etc/rc.d/rc.sysinit,/etc/rc.d/init.d/functions,/etc/fstab}; do l1=`grep '^#' $file | wc -l` l2=`grep '^[[:space:]]\+$' $file | wc -l` let sum1+=$l1 let sum2+=$l2 done echo "Total # lines: $sum1" echo "Total blank lines: $sum2" [root@localhost bin]# bash sum1.sh grep: /etc/rc.d/rc.sysinit: No such file or directory # CentOS7没有该文件 grep: /etc/rc.d/rc.sysinit: No such file or directory Total # lines: 38 Total blank lines: 3 [root@localhost bin]# bash sum1.sh # 在CentOS6.5上运行结果 Total # lines: 91 Total blank lines: 6
十一、写一个脚本,显示当前系统上全部默认shell为bash的用户的用户名、UID以及此类全部用户的UID之和;
[root@localhost bin]# vim sumuid.sh #!/bin/bash # 变量user是存放全部符合条件的uid # for循环是统计全部的uid之和,结果传递到sum # username_id是存放全部符合条件的username:uid # \n 是换行输出,目的为了输出对齐。 declare -i sum=0 user=$(grep '/bin/bash$' /etc/passwd | cut -d : -f 3) username_id=$(grep '/bin/bash$' /etc/passwd | cut -d : -f 1,3) for i in $user;do username=`echo $i | cut -d : -f 1` uid=`echo $i | cut -d : -f 3` let sum+=$uid done echo -e "当前系统上全部默认shell为bash的用户有如下列表:\n$username_id" echo "以上全部的UID之和为: $sum" ~ [root@localhost bin]# bash sumuid.sh 当前系统上全部默认shell为bash的用户有如下列表: root:0 terry:1000 user1:1001 user2:1002 user3:1003 ...(中间省略)... visitor19:1033 visitor20:1034 以上全部的UID之和为: 35595
十二、写一个脚本,显示当前系统上全部,拥有附加组的用户的用户名;并说明共有多少个此类用户;
[root@localhost bin]# vim guserlist1.sh #!/bin/bash declare -i count=0 userlist=$(cat /etc/passwd | cut -d : -f 1) for username in $userlist;do id $username | cut -d ' ' -f 3 |grep [,] &> /dev/null if [ $? -eq 0 ] then echo "$username" count=$[$count+1] fi done echo "拥有附加组的用户数为:$count"
[root@localhost bin]# bash guserlist1.sh postfix 拥有附加组的用户数为:1
1三、建立一个由至少两个物理卷组成的大小为20G的卷组;要求,PE大小为8M;而在卷组中建立一个大小为5G的逻辑卷mylv1,格式化为ext4文件系统,开机自动挂载至/users目录,支持acl;
[root@localhost ~]# fdisk /dev/sdb # 分别建立两个10GB的分区sdb1 、sdb2,并将其文件系统更改成LVM Device Boot Start End Blocks Id System /dev/sdb1 2048 20973567 10485760 8e Linux LVM /dev/sdb2 20973568 41943039 10484736 8e Linux LVM # 建立两个pv [root@localhost ~]# pvcreate /dev/sdb1 Physical volume "/dev/sdb1" successfully created [root@localhost ~]# pvcreate /dev/sdb2 Physical volume "/dev/sdb2" successfully created [root@localhost ~]# pvs PV VG Fmt Attr PSize PFree /dev/sda2 centos lvm2 a-- 49.51g 44.00m /dev/sdb1 lvm2 --- 10.00g 10.00g /dev/sdb2 lvm2 --- 10.00g 10.00g # 建立vg,卷组名为myvg,并指定其PE大小为8M [root@localhost ~]# vgcreate -s 8m myvg /dev/sdb1 Volume group "myvg" successfully created [root@localhost ~]# vgextend myvg /dev/sdb2 Volume group "myvg" successfully extended [root@localhost ~]# vgdisplay --- Volume group --- VG Name myvg System ID Format lvm2 Metadata Areas 2 Metadata Sequence No 2 VG Access read/write VG Status resizable MAX LV 0 Cur LV 0 Open LV 0 Max PV 0 Cur PV 2 Act PV 2 VG Size 19.98 GiB PE Size 8.00 MiB Total PE 2558 Alloc PE / Size 0 / 0 Free PE / Size 2558 / 19.98 GiB VG UUID OcIY2r-SbI3-W9sk-z9OT-ZUT1-iiGo-X4tVYg # 在VG中建立名为mylv1,大小为5G的LV [root@localhost ~]# lvcreate -L 5G -n mylv1 myvg Logical volume "mylv1" created. [root@localhost ~]# lvdisplay --- Logical volume --- LV Path /dev/myvg/mylv1 LV Name mylv1 VG Name myvg LV UUID XvtKZT-15g3-Ajc2-yqLm-Wh3j-Pu2X-6MuvF5 LV Write Access read/write LV Creation host, time localhost.localdomain, 2016-10-09 22:16:52 +0800 LV Status available # open 0 LV Size 5.00 GiB Current LE 640 Segments 1 Allocation inherit Read ahead sectors auto - currently set to 8192 Block device 253:2 # 设置文件系统类型为ext4 [root@localhost ~]# mkfs -t ext4 /dev/myvg/mylv1 # 建立目录/users并将mylv1挂载至该目录 [root@localhost ~]# mkdir /users # 临时挂载的方式,该操做重启后失效,须要从新挂载 [root@localhost ~]# mount /dev/myvg/mylv1 /users [root@localhost ~]# df -lh Filesystem Size Used Avail Use% Mounted on /dev/mapper/myvg-mylv1 4.8G 20M 4.6G 1% /users [root@localhost ~]# umount /dev/myvg/mylv1 # 为了测试,先卸载临时挂载的文件系统 # 编辑/etc/fstab文件实现开机自动挂载,在最后一行加入如下内容: [root@localhost ~]# vim /etc/fstab /dev/myvg/mylv1 /users ext4 acl 0 0 # 验证结果:重启机器后查看,其中有一条显示已挂载 [root@localhost ~]# shutdown -r now [root@localhost ~]# mount /dev/mapper/myvg-mylv1 on /users type ext4 (rw,relatime,seclabel,data=ordered)
1四、新建用户magedu;其家目录为/users/magedu,然后su切换至此用户,复制多个文件至家目录;
# 新建用户magedu,并设置其家目录 [root@localhost ~]# useradd magedu -d /users/magedu [root@localhost ~]# cat /etc/passwd # 验证建立结果 magedu:x:1035:1035::/users/magedu:/bin/bash # 切换至magedu用户并复制文件至该用户家目录 [root@localhost ~]# su - magedu [magedu@localhost ~]$ cp -r /etc/pam.d ~ [magedu@localhost ~]$ cp -r /etc/fstab ~ [magedu@localhost ~]$ ll ~ total 8 -rw-r--r--. 1 magedu magedu 542 Oct 9 22:40 fstab drwxr-xr-x. 2 magedu magedu 4096 Oct 9 22:38 pam.d
1五、扩展mylv1至9G,确保扩展完成后原有数据彻底可用;
# 操做前先将已挂载的逻辑卷卸载 [magedu@localhost ~]$ umount /dev/myvg/mylv1 umount: /users: umount failed: Operation not permitted # 提示权限不足须要切换至管理员用户操做 [magedu@localhost ~]$ su - Password: Last login: Sun Oct 9 22:29:17 CST 2016 from 192.168.178.1 on pts/2 [root@localhost ~]# umount /dev/myvg/mylv1 umount: /users: target is busy. (In some cases useful info about processes that use the device is found by lsof(8) or fuser(1)) # 依然提示挂载目录繁忙没法卸载,尝试logout再登陆后,卸载完成 [root@localhost ~]# umount /dev/myvg/mylv1 # 扩展mylv1至9G,因为第一步操做时给了7G,不足,能够再次扩展 # 此处9G前没有+ 表明总容量扩展至9G,若是前面加+号,会在原来容量基础上+9G [root@localhost ~]# lvextend -L 7G /dev/myvg/mylv1 Size of logical volume myvg/mylv1 changed from 5.00 GiB (640 extents) to 7.00 GiB (896 extents). Logical volume mylv1 successfully resized. [root@localhost ~]# lvs LV VG Attr LSize Pool Origin Data% Meta% Move Log Cpy%Sync Convert mylv1 myvg -wi-a----- 7.00g [root@localhost ~]# lvextend -L 9G /dev/myvg/mylv1 Size of logical volume myvg/mylv1 changed from 7.00 GiB (896 extents) to 9.00 GiB (1152 extents). Logical volume mylv1 successfully resized. [root@localhost ~]# lvs LV VG Attr LSize Pool Origin Data% Meta% Move Log Cpy%Sync Convert mylv1 myvg -wi-a----- 9.00g # 扩展好后,从新挂载文件系统,查看里面文件是否存在且可用 [root@localhost ~]# mount /dev/myvg/mylv1 /users [root@localhost ~]# ll /users/magedu total 8 -rw-r--r--. 1 magedu magedu 542 Oct 9 22:40 fstab drwxr-xr-x. 2 magedu magedu 4096 Oct 9 22:38 pam.d
1六、缩减mylv1至7G,确保缩减完成后原有数据彻底可用;
# 对文件系统属性进行操做时先进行卸载 [root@localhost ~]# umount /dev/myvg/mylv1 # 使用e2fsck强制进行检测或修复文件系统 [root@localhost ~]# e2fsck -f /dev/myvg/mylv1 e2fsck 1.42.9 (28-Dec-2013) Pass 1: Checking inodes, blocks, and sizes Pass 2: Checking directory structure Pass 3: Checking directory connectivity Pass 4: Checking reference counts Pass 5: Checking group summary information /dev/myvg/mylv1: 52/327680 files (0.0% non-contiguous), 58497/1310720 blocks # 先修改文件系统大小为7G,再把逻辑卷大小修改成7G [root@localhost ~]# resize2fs /dev/myvg/mylv1 7G resize2fs 1.42.9 (28-Dec-2013) Resizing the filesystem on /dev/myvg/mylv1 to 1835008 (4k) blocks. The filesystem on /dev/myvg/mylv1 is now 1835008 blocks long. [root@localhost ~]# lvs LV VG Attr LSize Pool Origin Data% Meta% Move Log Cpy%Sync Convert mylv1 myvg -wi-a----- 9.00g # 文件系统大小修改后,lvs显示依然是9G [root@localhost ~]# lvreduce -L 7G /dev/myvg/mylv1 WARNING: Reducing active logical volume to 7.00 GiB THIS MAY DESTROY YOUR DATA (filesystem etc.) Do you really want to reduce mylv1? [y/n]: y Size of logical volume myvg/mylv1 changed from 9.00 GiB (1152 extents) to 7.00 GiB (896 extents). Logical volume mylv1 successfully resized. [root@localhost ~]# lvs LV VG Attr LSize Pool Origin Data% Meta% Move Log Cpy%Sync Convert mylv1 myvg -wi-a----- 7.00g [root@localhost ~]# mount /dev/myvg/mylv1 /users [root@localhost ~]# ll /users/magedu total 8 -rw-r--r--. 1 magedu magedu 542 Oct 9 22:40 fstab drwxr-xr-x. 2 magedu magedu 4096 Oct 9 22:38 pam.d
1七、对mylv1建立快照,并经过备份数据;要求保留原有的属主属组等信息;
# 考虑到mylv1大小为7G,而且数据备份中可能有数据变更,建立10G大小的快照 # -s指明快照,-n是名字,-p是权限,r是只读 [root@localhost ~]# lvcreate -L 10G -p r -s -n mylv1-snap /dev/myvg/mylv1 Reducing COW size 10.00 GiB down to maximum usable size 7.03 GiB. Logical volume "mylv1-snap" created. [root@localhost ~]# lvdisplay --- Logical volume --- LV Path /dev/myvg/mylv1 LV Name mylv1 VG Name myvg LV UUID XvtKZT-15g3-Ajc2-yqLm-Wh3j-Pu2X-6MuvF5 LV Write Access read/write LV Creation host, time localhost.localdomain, 2016-10-09 22:16:52 +0800 LV snapshot status source of mylv1-snap [active] LV Status available # open 1 LV Size 7.00 GiB Current LE 896 Segments 1 Allocation inherit Read ahead sectors auto - currently set to 8192 Block device 253:2 --- Logical volume --- LV Path /dev/myvg/mylv1-snap LV Name mylv1-snap VG Name myvg LV UUID ynizpC-ftB1-BAmf-csBt-OV6z-aylr-szJMRb LV Write Access read only LV Creation host, time localhost.localdomain, 2016-10-09 23:13:25 +0800 LV snapshot status active destination for mylv1 LV Status available # open 0 LV Size 7.00 GiB Current LE 896 COW-table size 7.03 GiB COW-table LE 900 Allocated to snapshot 0.00% Snapshot chunk size 4.00 KiB Segments 1 Allocation inherit Read ahead sectors auto - currently set to 8192 Block device 253:5
# 一般建立快照的主要目的是作备份,可写一个简单的备份脚原本自动建立快照,而后挂载进行备份, # 备份完成后又自动卸载和删除。 # 由于快照建立速度很是快,因此使用快照来备份做业不只能够解决一致性问题, 也可减小备份时间 # 快照须要挂载后才能看到其内容,而快照只是保存修改前那一刻的状态,不会自动更新, # 当备份操做完成后,应该删除快照,以节省空间及减轻系统的I/O负担 # 快照的查看与备份恢复 [root@localhost ~]# mount /dev/myvg/mylv1-snap /backup mount: /dev/mapper/myvg-mylv1--snap is write-protected, mounting read-only [root@localhost ~]# ll /users/magedu # 原文件里的内容 total 8 -rw-r--r--. 1 magedu magedu 542 Oct 9 22:40 fstab drwxr-xr-x. 2 magedu magedu 4096 Oct 9 22:38 pam.d [root@localhost ~]# ll /backup/magedu/ # 快照里的内容,跟原文件内容是一直的 total 8 -rw-r--r--. 1 magedu magedu 542 Oct 9 22:40 fstab drwxr-xr-x. 2 magedu magedu 4096 Oct 9 22:38 pam.d [root@localhost ~]# cp -a /backup/magedu/ /tmp #因为快照只读,备份快照内容至/tmp/ [root@localhost ~]# ls /tmp/ filetype.sh ks-script-pw2v6q magedu pam.d.tar uidex.sh yum.log [root@localhost users]# rm -rf magedu # 删除原文件内容并添加一些新文件 [root@localhost users]# mkdir newfolder [root@localhost users]# touch hello.txt [root@localhost users]# ll total 20 -rw-r--r--. 1 root root 0 Oct 9 23:33 hello.txt drwx------. 2 root root 16384 Oct 9 22:19 lost+found drwxr-xr-x. 2 root root 4096 Oct 9 23:33 newfolder [root@localhost ~]# ls /backup/magedu # 不管对原文件如何操做,快照的内容依然不变 fstab pam.d [root@localhost ~]# ll /tmp/magedu/ total 8 -rw-r--r--. 1 magedu magedu 542 Oct 9 22:40 fstab drwxr-xr-x. 2 magedu magedu 4096 Oct 9 22:38 pam.d [root@localhost ~]# cp -a /tmp/magedu/ /users/ # 将快照内容恢复至原文件位置 [root@localhost ~]# ll /users total 24 -rw-r--r--. 1 root root 0 Oct 9 23:33 hello.txt #新建立的文件依然存在 drwx------. 2 root root 16384 Oct 9 22:19 lost+found drwx------. 4 magedu magedu 4096 Oct 9 22:48 magedu #恢复的文件,时间等属性不变 drwxr-xr-x. 2 root root 4096 Oct 9 23:33 newfolder #新建立的文件依然存在 [root@localhost ~]# ll /users/magedu #从备份恢复回来的原文件,时间等属性不变 total 8 -rw-r--r--. 1 magedu magedu 542 Oct 9 22:40 fstab drwxr-xr-x. 2 magedu magedu 4096 Oct 9 22:38 pam.d # 备份还原操做完成后,快照不须要存在,进行卸载删除 [root@localhost ~]# umount /dev/myvg/mylv1-snap [root@localhost ~]# lvremove /dev/myvg/mylv1-snap Do you really want to remove active logical volume mylv1-snap? [y/n]: y Logical volume "mylv1-snap" successfully removed [root@localhost ~]# lvs LV VG Attr LSize Pool Origin Data% Meta% Move Log Cpy%Sync Convert root centos -wi-ao---- 47.46g swap centos -wi-ao---- 2.00g mylv1 myvg -wi-ao---- 7.00g