20150901日课程作业（挂载硬盘，手动创建SWAP分区，链接文件，磁盘及文件系统相关管理命令）
一、作业（练习）内容：
1、复习本次课程所讲的内容；
硬链接：ln SRC DEST
2个文件路径指向同一个Inod
不能跨文件系统，目录不支持硬链接，创建硬链接会增加inod引用计数
软链接：ln -s SRC DEST
软链接是独立的文件，指向被链接的文件，其大小不是被链接文件的大小，而是指向被链接文件的文件路径的字符串字节大小，可以看作是原文件的快捷方式
硬盘挂载：
列出当前磁盘情况:fdisk -l
分区：fdisk /dev/DEVICE
通知内核更新分区信息：partx -a /dev/DEVICE
格式化：mkfs.FILETYPE /dev/DEVICE,mke2fs -t FILETYPE /dev/DEVICE
挂载：mount /dev/DEVICE MOUNT_POINT
添加开机自动挂载：/etc/fstab
e2label,tune2fs,dumpe2fs,fsck,df,du,fuser,free,blkid
手动创建SWAP分区：
swap有两种：
1.使用分区做为SWAP
2.使用文件做为SWAP
使用分区做为SWAP比较好，速度比文件的快，也不容易产生磁盘碎片所有应该尽量使用分区作为SWAP
2、总结整理磁盘管理及文件系统管理中设计的各种命令的使用，并附注一定的示例
①、新建一个2G的交换分区
使用分区作为SWAP分区：
[root@localhost ~]# free -h
total used free shared buffers cached
Mem: 981M 178M 802M 240K 10M 53M
-/+ buffers/cache: 114M 867M
Swap: 2.0G 0B 2.0G
[root@localhost ~]# fdisk -l
Disk /dev/sda: 107.4 GB, 107374182400 bytes
255 heads, 63 sectors/track, 13054 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00004c84
Device Boot Start End Blocks Id System
/dev/sda1 * 1 64 512000 83 Linux
Partition 1 does not end on cylinder boundary.
/dev/sda2 64 3889 30720000 83 Linux
/dev/sda3 3889 4150 2097152 82 Linux swap / Solaris
/dev/sda4 4150 13055 71527424 5 Extended
/dev/sda5 4150 13055 71526400 83 Linux
Disk /dev/sdb: 21.5 GB, 21474836480 bytes
255 heads, 63 sectors/track, 2610 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0xc5a5780c
Device Boot Start End Blocks Id System
/dev/sdb1 1 1306 10490413+ 83 Linux
[root@localhost ~]# fdisk /dev/sdb
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
Command action
e extended
p primary partition (1-4)
p
Partition number (1-4): 2
First cylinder (1307-2610, default 1307):
Using default value 1307
Last cylinder, +cylinders or +size{K,M,G} (1307-2610, default 2610): +2G
Command (m for help): W
The partition table has been altered!
Calling ioctl() to re-read partition table.
WARNING: Re-reading the partition table failed with error 16: Device or resource busy.
The kernel still uses the old table. The new table will be used at
the next reboot or after you run partprobe(8) or kpartx(8)
Syncing disks.
[root@localhost ~]# fdisk /dev/sdb
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): l
0 Empty 24 NEC DOS 81 Minix / old Lin bf Solaris
1 FAT12 39 Plan 9 82 Linux swap / So c1 DRDOS/sec (FAT-
2 XENIX root 3c PartitionMagic 83 Linux c4 DRDOS/sec (FAT-
3 XENIX usr 40 Venix 80286 84 OS/2 hidden C: c6 DRDOS/sec (FAT-
4 FAT16 <32M 41 PPC PReP Boot 85 Linux extended c7 Syrinx
5 Extended 42 SFS 86 NTFS volume set da Non-FS data
6 FAT16 4d QNX4.x 87 NTFS volume set db CP/M / CTOS / .
7 HPFS/NTFS 4e QNX4.x 2nd part 88 Linux plaintext de Dell Utility
8 AIX 4f QNX4.x 3rd part 8e Linux LVM df BootIt
9 AIX bootable 50 OnTrack DM 93 Amoeba e1 DOS access
a OS/2 Boot Manag 51 OnTrack DM6 Aux 94 Amoeba BBT e3 DOS R/O
b W95 FAT32 52 CP/M 9f BSD/OS e4 SpeedStor
c W95 FAT32 (LBA) 53 OnTrack DM6 Aux a0 IBM Thinkpad hi eb BeOS fs
e W95 FAT16 (LBA) 54 OnTrackDM6 a5 FreeBSD ee GPT
f W95 Ext'd (LBA) 55 EZ-Drive a6 OpenBSD ef EFI (FAT-12/16/
10 OPUS 56 Golden Bow a7 NeXTSTEP f0 Linux/PA-RISC b
11 Hidden FAT12 5c Priam Edisk a8 Darwin UFS f1 SpeedStor
12 Compaq diagnost 61 SpeedStor a9 NetBSD f4 SpeedStor
14 Hidden FAT16 <3 63 GNU HURD or Sys ab Darwin boot f2 DOS secondary
16 Hidden FAT16 64 Novell Netware af HFS / HFS+ fb VMware VMFS
17 Hidden HPFS/NTF 65 Novell Netware b7 BSDI fs fc VMware VMKCORE
18 AST SmartSleep 70 DiskSecure Mult b8 BSDI swap fd Linux raid auto
1b Hidden W95 FAT3 75 PC/IX bb Boot Wizard hid fe LANstep
1c Hidden W95 FAT3 80 Old Minix be Solaris boot ff BBT
1e Hidden W95 FAT1
Command (m for help): t
Partition number (1-4): 2
Hex code (type L to list codes): 82
Changed system type of partition 2 to 82 (Linux swap / Solaris)
Command (m for help): p
Disk /dev/sdb: 21.5 GB, 21474836480 bytes
255 heads, 63 sectors/track, 2610 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0xc5a5780c
Device Boot Start End Blocks Id System
/dev/sdb1 1 1306 10490413+ 83 Linux
/dev/sdb2 1307 1568 2104515 82 Linux swap / Solaris
Command (m for help): w
The partition table has been altered!
Calling ioctl() to re-read partition table.
WARNING: Re-reading the partition table failed with error 16: Device or resource busy.
The kernel still uses the old table. The new table will be used at
the next reboot or after you run partprobe(8) or kpartx(8)
Syncing disks.
[root@localhost ~]# partx -a /dev/sdb
BLKPG: Device or resource busy
error adding partition 1
BLKPG: Device or resource busy
error adding partition 2
[root@localhost ~]# partx -a /dev/sdb
BLKPG: Device or resource busy
error adding partition 1
BLKPG: Device or resource busy
error adding partition 2
[root@localhost ~]# cat /proc/partitions
major minor #blocks name
8 0 104857600 sda
8 1 512000 sda1
8 2 30720000 sda2
8 3 2097152 sda3
8 4 1 sda4
8 5 71526400 sda5
8 16 20971520 sdb
8 17 10490413 sdb1
8 18 2104515 sdb2
[root@localhost ~]#
[root@localhost ~]# mkswap /dev/sdb2
Setting up swapspace version 1, size = 2104508 KiB
no label, UUID=0acec160-247f-4d03-91ee-dc7129c708aa
[root@localhost ~]# file /dev/sdb2
/dev/sdb2: block special
[root@localhost ~]# swapon /dev/sdb2
[root@localhost ~]# swapon -s
Filename Type Size Used Priority
/dev/sda3 partition 2097148 0 -1
/dev/sdb2 partition 2104508 0 -2
[root@localhost ~]# free
total used free shared buffers cached
Mem: 1004772 185608 819164 240 11756 55404
-/+ buffers/cache: 118448 886324
Swap: 4201656 0 4201656
[root@localhost ~]# echo "UUID=69465a2e-7ab3-4d44-a755-10b3ffde416c swap swap defaults 0 0">>/etc/fstab
[root@localhost ~]# mount -a
[root@localhost ~]#
使用文件作为swap:
[root@localhost ~]# dd if=/dev/zero of=/tmp/swapfile bs=1024 count=2048000 2048000+0 records in 2048000+0 records out 2097152000 bytes (2.1 GB) copied, 8.52182 s, 246 MB/s [root@localhost ~]# file /tmp/swapfile /tmp/swapfile: data [root@localhost ~]# mkswap /tmp/swapfile mkswap: /tmp/swapfile: warning: don't erase bootbits sectors on whole disk. Use -f to force. Setting up swapspace version 1, size = 2047996 KiB no label, UUID=9c57a77d-03d8-4eed-adc6-27b6404dd70f [root@localhost ~]# file /tmp/swapfile /tmp/swapfile: Linux/i386 swap file (new style) 1 (4K pages) size 511999 pages [root@localhost ~]# swapon /tmp/swapfile [root@localhost ~]# swapon -s Filename Type Size Used Priority /dev/sda3 partition 2097148 0 -1 /dev/sdb2 partition 2104508 0 -2 /tmp/swapfile file 2047996 0 -3 [root@localhost ~]# free -h total used free shared buffers cached Mem: 981M 915M 66M 240K 5.2M 768M -/+ buffers/cache: 141M 839M Swap: 6.0G 0B 6.0G [root@localhost ~]# blkid /tmp/swapfile /tmp/swapfile: UUID="9c57a77d-03d8-4eed-adc6-27b6404dd70f" TYPE="swap" [root@localhost ~]# echo "UUID=9c57a77d-03d8-4eed-adc6-27b6404dd70f swap swap defaults 0 0" >>/etc/fstab [root@localhost ~]# mount -a [root@localhost ~]#
②df,du,fuesr,
[root@localhost ~]# df -TH Filesystem Type Size Used Avail Use% Mounted on /dev/sda2 ext4 31G 2.8G 27G 10% / tmpfs tmpfs 515M 0 515M 0% /dev/shm /dev/sda1 ext4 500M 38M 436M 8% /boot /dev/sda5 ext4 72G 2.2G 67G 4% /usr /dev/sdb1 ext4 11G 24M 9.9G 1% /mydata [root@localhost ~]# df -ia Filesystem Inodes IUsed IFree IUse% Mounted on /dev/sda2 1921360 9287 1912073 1% / proc 0 0 0 - /proc sysfs 0 0 0 - /sys devpts 0 0 0 - /dev/pts tmpfs 125596 1 125595 1% /dev/shm /dev/sda1 128016 38 127978 1% /boot /dev/sda5 4472832 79188 4393644 2% /usr /dev/sdb1 655776 12 655764 1% /mydata none 0 0 0 - /proc/sys/fs/binfmt_misc [root@localhost ~]# du -sh ~ 160K /root [root@localhost ~]# du -a ~ 4 /root/mq 8 /root/install.log.syslog 4 /root/.tcshrc 4 /root/.bash_logout 0 /root/?a 0 /root/2dev 0 /root/4dev 4 /root/test/test.file 8 /root/test 0 /root/a 0 /root/aaa 0 /root/,a 0 /root/1dev 4 /root/11 36 /root/install.log 4 /root/anaconda-ks.cfg 0 /root/5dev 4 /root/.bashrc 4 /root/.cshrc 48 /root/.bash_history 4 /root/.bash_profile 4 /root/install.sh 12 /root/.nihao.swp 0 /root/3dev 8 /root/.viminfo 160 /root [root@localhost ~]# [root@localhost ~]# umount /mydata/ umount: /mydata: device is busy. (In some cases useful info about processes that use the device is found by lsof(8) or fuser(1)) [root@localhost ~]# fuser -v /mydata USER PID ACCESS COMMAND /mydata: root 2253 ..c.. bash [root@localhost ~]# ps aux|grep 2253 root 2253 0.0 0.1 108432 1884 pts/1 Ss+ 11:41 0:00 -bash root 2282 0.0 0.0 103308 844 pts/0 S+ 11:43 0:00 grep 2253 [root@localhost ~]# fuser -k /mydata /mydata: 2253c