|
分区 Linux下最常用的分区工具是fdisk操作简单，易用，但使用这个分区工具最多分区分15个。 fdisk –l 查看系统上所有磁盘分区信息。 fdisk –l /dev/sd* [root@www ~]# fdisk -l /dev/sdb Disk /dev/sdb: 21.5 GB, 21474836480 bytes 255 heads, 63 sectors/track, 2610 cylinders Units = cylinders of 16065 * 512 = 8225280bytes Sector size (logical/physical): 512 bytes /512 bytes I/O size (minimum/optimal): 512 bytes / 512bytes Disk identifier: 0x07a95eb7
Device Boot Start End Blocks Id System fdisk /dev/sd* 几个常见的参数 d delete a partition 删除分区 l list known partition types 各分区类型所对应的systemID n add a new partition 创建一个新分区 p print the partition table 打印出分区表相当于fdisk–l /dev/sd* q quit without saving changes 不保存当前操作退出fdisk分区工具 t change a partition's system id改变一个分区的system ID w write table to disk and exit 保存当前操作退出fdisk 创建实例[root@www ~]# fdisk/dev/sdb 对/dev/sdb进行分区
WARNING: DOS-compatible mode is deprecated.It's strongly recommended to switch off the mode (command 'c') and change display units to sectors (command 'u').
Command (m for help): n n表示新建一个分区 Command action e extended 表示扩展分区 p primary partition (1-4) 表示主分区 p 输入批表示创建一个主分区 Partition number (1-4): 1输入分区编号/dev/sdb1 First cylinder (1-2610, default 1): 敲回车键表示从第一个柱面开始 Using default value 1 Last cylinder, +cylinders or +size{K,M,G}(1-2610, default 2610): +5G 分区大小为5G这里也可以键入到第几柱面
Command (m for help): p 查看该磁盘的分区信息
Disk /dev/sdb: 21.5 GB, 21474836480 bytes 255 heads, 63 sectors/track, 2610 cylinders Units = cylinders of 16065 * 512 = 8225280bytes Sector size (logical/physical): 512 bytes /512 bytes I/O size (minimum/optimal): 512 bytes / 512bytes Disk identifier: 0x07a95eb7
设备名称 开始柱面 结束柱面 块大小system Id 类型 Device Boot Start End Blocks Id System /dev/sdb1 1 654 5253223+ 83 Linux Command (m for help): w 保存并退出 Thepartition table has been altered!
Callingioctl() to re-read partition table. Syncingdisks. 查看分区操作是否写入系统内核[root@www ~]# cat/proc/partitions major minor #blocks name
8 0 26214400 sda 8 1 512000 sda1 8 2 25701376 sda2 8 16 20971520 sdb 8 17 5253223 sdb1 内核能读取到硬盘分区表但是有时内核会读取不到这时就使用partx命令命令如下 [root@www~]# partx -a /dev/sdb1 /dev/sdb 创建文件系统使用mkfsmkfs.ext[2|3|4],mke2fs来进行文件系统的创建一般使用mke2fsmkfs –t ext2= mkfs.ext2 = mke2fs –t ext2 mkfs –t ext3= mkfs.ext3 = mke2fs –t ext3 mkfs –t ext4= mkfs.ext4 = mke2fs –t ext4 mke2fsmke2fs –t type Device:创建什么类型的文件系统 mke2fs –b{1024|2048|4096} Device 分区的块大小 [root@www ~]# mke2fs -text4 -b 2048 /dev/sdc2 mke2fs 1.41.12 (17-May-2010) Filesystem label= OS type: Linux Block size=2048 (log=1) Fragment size=2048 (log=1) Stride=0 blocks, Stripe width=0 blocks 197880 inodes, 1578386 blocks 78919 blocks (5.00%) reserved for the superuser First data block=0 Maximum filesystem blocks=538968064 97 block groups 16384 blocks per group, 16384 fragments pergroup 2040 inodes per group Superblock backups stored on blocks: 16384,49152, 81920, 114688, 147456, 409600, 442368, 802816, 1327104
Writing inode tables: done Creating journal (32768 blocks): done Writing superblocks and filesystemaccounting information: done
This filesystem will be automaticallychecked every 24 mounts or 180 days, whichever comes first. Use tune2fs -c or -i to override. [root@www ~]# tune2fs -l/dev/sdc2 | grep "Block size" Block size: 2048 [root@www ~]# blkid/dev/sdc2 /dev/sdc2:UUID="ac40a50d-ddee-44b0-a6a8-481e7b33a548" TYPE="ext4"
mke2fs创建默认是ext2 [root@www ~]# mke2fs /dev/sdb1 mke2fs 1.41.12 (17-May-2010) Filesystem label= OS type: Linux Block size=4096 (log=2) Fragment size=4096 (log=2) Stride=0 blocks, Stripe width=0 blocks 328656 inodes, 1313305 blocks 65665 blocks (5.00%) reserved for the superuser First data block=0 Maximum filesystem blocks=1346371584 41 block groups 32768 blocks per group, 32768 fragments pergroup 8016 inodes per group Superblock backups stored on blocks: 32768,98304, 163840, 229376, 294912, 819200, 884736
Writing inode tables: done Writing superblocks and filesystemaccounting information: done
This filesystem will be automaticallychecked every 24 mounts or 180 days, whichever comes first. Use tune2fs -c or -i to override. mke2fs配置文件/etc/mke2fs.conf[defaults] base_features = sparse_super,filetype,resize_inode,dir_index,ext_attr 默认使用ext2文件系统 blocksize = 4096 默认块大小 inode_size = 256 inode_ratio = 16384 将下面的features后的赋值补充到base_features后面系统默认分区的文件系统就是ext3或ext4 [fs_types] ext3 = { features = has_journal } ext4 = { features =has_journal,extent,huge_file,flex_bg,uninit_bg,dir_nlink,extra_isize inode_size = 256 {
tune2fs -l [DEVICE] 其显示的信息十分丰富查看其块大小 [root@www ~]# tune2fs -l/dev/sdb1 | grep "Block size" Block size: 4096
blkid命令查看UUID和文件系统类型[root@www ~]# blkid /dev/sdb1 /dev/sdb1:UUID="8595c196-9c41-4bfb-8b76-4930705e6c12" TYPE="ext2" 挂载文件系统mount –t type Device 挂载点 mount命令查看当前系统挂载的文件系统 [root@www ~]# mount /dev/mapper/vg_centos-lv_root on / typeext4 (rw) proc on /proc type proc (rw) sysfs on /sys type sysfs (rw) devpts on /dev/pts type devpts(rw,gid=5,mode=620) tmpfs on /dev/shm type tmpfs (rw) /dev/sda1 on /boot type ext4 (rw) none on /proc/sys/fs/binfmt_misc typebinfmt_misc (rw) sunrpc on /var/lib/nfs/rpc_pipefs typerpc_pipefs (rw) nfsd on /proc/fs/nfsd type nfsd (rw) /etc/mtab文件也可以查看当前系统的挂载情况mount命令所看到的结果均来自此文件 [root@www ~]# cat/etc/mtab /dev/mapper/vg_centos-lv_root / ext4 rw 0 0 proc /proc proc rw 0 0 sysfs /sys sysfs rw 0 0 devpts /dev/pts devpts rw,gid=5,mode=620 00 tmpfs /dev/shm tmpfs rw 0 0 /dev/sda1 /boot ext4 rw 0 0 none /proc/sys/fs/binfmt_misc binfmt_miscrw 0 0 sunrpc /var/lib/nfs/rpc_pipefs rpc_pipefsrw 0 0 nfsd /proc/fs/nfsd nfsd rw 0 0 使用mount命令挂载当时有效，系统重启失效将要挂载的文件系统吸入/etc/fstab文件中 LVMLVM是逻辑盘卷管理Logical VolumeManager，它是Linux环境下对磁盘分区进行管理的一种机制，LVM是建立在硬盘和分区之上的一个逻辑层，来提高磁盘分区管理的灵活性 LVM创建顺序是PV——〉VG——〉LV 不知道大家注意没有使用默认安装CentOS时系统默认使用的LVM 创建前准备将分区的system ID改成8e(Linux LVM) [root@www ~]# fdisk/dev/sdc
Command (m for help): t Partition number (1-4): 2 Hex code (type L to list codes): 8e Changed system type of partition 2 to 8e(Linux LVM)
Command (m for help): p
Disk /dev/sdc: 21.5 GB, 21474836480 bytes 255 heads, 63 sectors/track, 2610 cylinders Units = cylinders of 16065 * 512 = 8225280bytes Sector size (logical/physical): 512 bytes /512 bytes I/O size (minimum/optimal): 512 bytes / 512bytes Disk identifier: 0xbeaf1b91
Device Boot Start End Blocks Id System /dev/sdc1 1 654 5253223+ 83 Linux /dev/sdc2 655 1047 3156772+ 8e Linux LVM LVM的创建流程
[root@www ~]# pvcreate/dev/sdc2 Physical volume "/dev/sdc2" successfully created [root@www ~]# pvcreate/dev/sdb1 Physical volume "/dev/sdb1" successfully created 2. [root@www ~]# vgcreate testvg/dev/sdb1 /dev/sdc2 Volume group "testvg" successfully created 3. [root@www ~]# lvcreate -L 5G -ntestlv testvg Logical volume "testlv" created 验证lv创建起没有 [root@www ~]# lvdisplay/dev/testvg/testlv ---Logical volume --- LVPath /dev/testvg/testlv LV Name testlv VG Name testvg LVUUID UiuqXG-22fG-qKoz-dFzw-oHvP-OZYY-aOII0F LVWrite Access read/write LVCreation host, time www.linux.com, 2014-09-26 20:21:14 +0800 LVStatus available #open 0 LVSize 5.00 GiB Current LE 1280 Segments 1 Allocation inherit Read ahead sectors auto -currently set to 256 Block device 253:2 创建文件系统 [root@www ~]# mke2fs -text4 /dev/testvg/testlv 挂载文件系统
/dev/mapper/vg_centos-lv_rooton / type ext4 (rw) procon /proc type proc (rw) sysfson /sys type sysfs (rw) devptson /dev/pts type devpts (rw,gid=5,mode=620) tmpfson /dev/shm type tmpfs (rw) /dev/sda1on /boot type ext4 (rw) noneon /proc/sys/fs/binfmt_misc type binfmt_misc (rw) sunrpcon /var/lib/nfs/rpc_pipefs type rpc_pipefs (rw) nfsdon /proc/fs/nfsd type nfsd (rw) gvfs-fuse-daemonon /root/.gvfs type fuse.gvfs-fuse-daemon (rw,nosuid,nodev) /dev/sr0on /media/CentOS_6.4_Final type iso9660(ro,nosuid,nodev,uhelper=udisks,uid=0,gid=0,iocharset=utf8,mode=0400,dmode=0500) /dev/mapper/testvg-testlvon /mnt type ext4 (rw) LVM详细使用介绍vg
准备一个pv [root@www ~]# pvcreate /dev/sdb2 Physical volume "/dev/sdb2" successfully created 扩展vg的容量 使用vgextend 命令 vgextend vgname Device [root@www ~]# vgextendtestvg /dev/sdb2 Volume group "testvg" successfully extended [root@www ~]# vgs Couldn't find device with uuid 2QpQ6S-B9Oz-7PB1-fIKo-Lhdw-h00t-3EtX00. VG #PV #LV #SN Attr VSize VFree VG 2 0 0wz-pn- 8.02g 8.02g testvg 3 1 0 wz--n- 15.02g 10.02g vg_centos 1 2 0wz--n- 24.51g 0 2. vg卷组的缩减 将要移除pv上的数据移动到其他pv上去 [root@www ~]# pvmove/dev/sdb1 /dev/sdb1: Moved: 0.1% /dev/sdb1: Moved: 64.8% /dev/sdb1: Moved: 100.0% vgreduce命令缩减vg vgreduce vgname Device [root@www ~]# vgreducetestvg /dev/sdb1 Removed "/dev/sdb1" from volume group "testvg" 3. 删除vg卷组 [root@www ~]# vgremove testvg Volume group "testvg" successfully removed lvlv的扩展 首先确定lv所在的卷组的空间是不是足够多 1. 扩展物理边界 [root@www ~]# lvextend -L+2G /dev/testvg/testlv Extending logical volume testlv to 7.00 GiB Logical volume testlv successfully resized 2. 扩展逻辑边界 [root@www ~]# resize2fs/dev/testvg/testlv resize2fs 1.41.12 (17-May-2010) Filesystem at /dev/testvg/testlv is mountedon /mnt; on-line resizing required old desc_blocks = 1, new_desc_blocks = 1 Performing an on-line resize of/dev/testvg/testlv to 1835008 (4k) blocks. The filesystem on /dev/testvg/testlv is now1835008 blocks long. 3. 验证lv扩展成功没 [root@www ~]# df -lh Filesystem Size Used Avail Use% Mounted on /dev/mapper/vg_centos-lv_root 23G 17G 4.2G 81% / tmpfs 935M 0 935M 0% /dev/shm /dev/sda1 485M 47M 414M 11% /boot /dev/mapper/testvg-testlv 6.9G 140M 6.5G 3% /mnt lv缩减 缩减lv之前一定要将其卸载并强行检测文件系统 [root@www ~]# umount/dev/testvg/testlv [root@www ~]# fsck -f /dev/testvg/testlvfsck 是文件系统检测工具加上 –f 参数表示强制检测 fsck from util-linux-ng 2.17.2 e2fsck 1.41.12 (17-May-2010) 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/mapper/testvg-testlv: 12/458752 files(0.0% non-contiguous), 64448/1835008 blocks 如果不检测文件系统在以后使用过程中可能会产生乱码
resizefs Device size [root@www ~]# resize2fs/dev/testvg/testlv 5G resize2fs 1.41.12 (17-May-2010) Resizing the filesystem on/dev/testvg/testlv to 1310720 (4k) blocks. 2. 缩减物理卷 [root@www ~]# lvreduce -L5G /dev/testvg/testlv WARNING: Reducing active logical volume to 5.00 GiB THIS MAY DESTROY YOUR DATA (filesystem etc.) Do you really want to reduce testlv? [y/n]:y Reducing logical volume testlv to 5.00 GiB Logical volume testlv successfully resized 3. 移除lv卷 a)卸载lv卷mount b)使用lvremove Device移除lv卷 [root@www ~]# umount /mnt [root@www ~]# lvremove/dev/testvg/testlv Do you really want toremove active logical volume testlv? [y/n]: y Logical volume"testlv" successfully removed 验证 [root@www ~]# lvs Couldn't find device with uuid 2QpQ6S-B9Oz-7PB1-fIKo-Lhdw-h00t-3EtX00. LV VG Attr LSize Pool Origin Data% Move LogCpy%Sync Convert lv_root vg_centos -wi-ao--- 22.57g lv_swap vg_centos -wi-ao--- 1.94g 注意lvreduce –L [+|-]size Device 表示在原卷大小的基础上加或者减少多少空间 lvreduce –L size Device 表示直接将原卷扩大多少空间。 LVM裁减顺序是 LV——〉VG——〉PV 此文档下载地址：http://down.51cto.com/data/1877421 (责任编辑：IT) |