文件系统
管理文件和目录的一套机制
1.文件存取
2.文件的查找
3.文件的大小、文件的多少。
4.一个目录可以存放多少个文件
5.文件的命名
6.一个分区可以多大
等
文件系统管理磁盘上的文件。
安装系统的时候,默认到底分多少个分区? / 根据实际情况,尽可能的大些 swap 4G /boot 500M == / swap /home /boot
autofs4 configfs exportfs fat jbd mbcache.ko nls
btrfs cramfs ext2 fscache jbd2 nfs squashfs
cachefiles dlm ext3 fuse jffs2 nfs_common ubifs
cifs ecryptfs ext4 gfs2 lockd nfsd udf
[root@station6 ~]#
nfs:network file system
mount -t cifs //192.168.1.2/share /mnt -o username=administrator%pwd
文件系统的组成:
superblock(超级块):记录此 file system 的整体信息,包括inode/block的总量、使用量、剩余量,以及文件系统的格式(第二块)
inode:记录文件的属性,一个文件占用一个inode,同时记录此文件的数据所在的 block 号码
[root@li ~]# blkid /dev/sda3: UUID="ed56849d-1483-4573-ab3a-df45a9ee2f78" TYPE="ext4" /dev/sda1: UUID="198d77c8-04ae-4ccb-91c4-fced324c2bad" TYPE="ext4" /dev/sda2: UUID="1a3b7a23-a08d-4874-8cce-0d2db0e4b21f" TYPE="swap" /dev/sdb5: UUID="9150a0ae-f691-424b-9d8e-a017d1ebe4e4" TYPE="ext4" /dev/sdc1: UUID="942af69a-e741-4b29-bb30-a81ab4ef2c70" TYPE="ext4" /dev/sdc2: UUID="df35355a-e0ac-4119-8993-5402fdb74360" TYPE="ext4" /dev/sdc3: LABEL="tanghailong" UUID="1930ebcc-fe91-4b9e-9b0a-719f765ebc24" TYPE="ext4" [root@li ~]#
parted配置gpt分区过程:
例如:1k的小文件很多,就会导致很多空间就浪费了)
-i:指定每个i节点有多少字节()
[root@li~]# mkfs.ext4 -L tanghailong /dev/sdc3 == [root@li ~]# blkid /dev/sda3: UUID="ed56849d-1483-4573-ab3a-df45a9ee2f78" TYPE="ext4" /dev/sda1: UUID="198d77c8-04ae-4ccb-91c4-fced324c2bad" TYPE="ext4" /dev/sda2: UUID="1a3b7a23-a08d-4874-8cce-0d2db0e4b21f" TYPE="swap" /dev/sdb5: UUID="9150a0ae-f691-424b-9d8e-a017d1ebe4e4" TYPE="ext4" /dev/sdc1: UUID="942af69a-e741-4b29-bb30-a81ab4ef2c70" TYPE="ext4" /dev/sdc2: UUID="df35355a-e0ac-4119-8993-5402fdb74360" TYPE="ext4" /dev/sdc3: LABEL="tanghailong" UUID="1930ebcc-fe91-4b9e-9b0a-719f765ebc24" TYPE="ext4" [root@li ~]#
[root@lichao520 ~]# dumpe2fs /dev/sdc3|more dumpe2fs 1.41.12 (17-May-2010) Filesystem volume name: tanghailong Last mounted on: <not available> Filesystem UUID: 1930ebcc-fe91-4b9e-9b0a-719f765ebc24 Filesystem magic number: 0xEF53 Filesystem revision #: 1 (dynamic) Filesystem features: has_journal ext_attr resize_inode dir_index f iletype extent flex_bg sparse_super large_file huge_file uninit_bg dir_ nlink extra_isize Filesystem flags: signed_directory_hash Default mount options: (none) Filesystem state: clean
修复文件系统前,建议先将文件系统卸载(umount)。再修复
[root@lichao520 ~]# fsck /dev/sdc1 fsck from util-linux-ng 2.17.2 e2fsck 1.41.12 (17-May-2010) /dev/sdc1 was not cleanly unmounted, check forced. 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 Inode bitmap differences: -(12--14) Fix<y>? yes 输入y,修复 /dev/sdc1: ***** FILE SYSTEM WAS MODIFIED ***** /dev/sdc1: 11/183264 files (0.0% non-contiguous), 28970/732160 blocks [root@lichao520 ~]# dumpe2fs /dev/sdc1|more dumpe2fs 1.41.12 (17-May-2010) Filesystem volume name: <none> Last mounted on: <not available> Filesystem UUID: 942af69a-e741-4b29-bb30-a81ab4ef2c70 Filesystem magic number: 0xEF53 Filesystem revision #: 1 (dynamic) Filesystem features: has_journal ext_attr resize_inode dir_index f iletype extent flex_bg sparse_super large_file huge_file uninit_bg dir_ nlink extra_isize Filesystem flags: signed_directory_hash Default mount options: (none) Filesystem state: clean Errors behavior: Continue Filesystem OS type: Linux Inode count: 183264 Block count: 732160 Reserved block count: 36608 Free blocks: 703190 Free inodes: 183253 First block: 0 Block size: 4096 Fragment size: 4096 [root@lichao520 ~]# 修复好,可以挂载使用 [root@lichao520 ~]# mount /dev/sdc1 /music/ [root@lichao520 ~]# df -Th Filesystem Type Size Used Avail Use% Mounted on /dev/sda3 ext4 18G 2.9G 14G 18% / tmpfs tmpfs 186M 260K 186M 1% /dev/shm /dev/sda1 ext4 485M 35M 426M 8% /boot /dev/sr0 iso9660 2.9G 2.9G 0 100% /media/RHEL_6.3 i386 Disc 1 /dev/sdc1 ext4 2.8G 69M 2.6G 3% /music [root@lichao520 ~]# === [root@lichao520 music]# cd [root@lichao520 ~]# umount /music/ [root@lichao520 ~]# dumpe2fs /dev/sdc1|more dumpe2fs 1.41.12 (17-May-2010) dumpe2fs: Bad magic number in super-block while trying to open /dev/sdc1 Couldn't find valid filesystem superblock. [root@lichao520 ~]# fsck -y /dev/sdc1 === [root@lichao520 ~]# fsck -y /dev/sdc1 fsck from util-linux-ng 2.17.2 e2fsck 1.41.12 (17-May-2010) fsck.ext2: Superblock invalid, trying backup blocks... /dev/sdc1 was not cleanly unmounted, check forced. 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/sdc1: ***** FILE SYSTEM WAS MODIFIED ***** /dev/sdc1: 11/183264 files (0.0% non-contiguous), 28970/732160 blocks [root@lichao520 ~]# [root@lichao520 ~]# dumpe2fs /dev/sdc1|more 修复后,可以查看,说明它是用来查看superblock里的信息的 ===
破坏/boot分区---》/dev/sda1 [root@localhost ~]# df -Th Filesystem Type Size Used Avail Use% Mounted on /dev/sda5 ext4 58G 1.8G 53G 4% / tmpfs tmpfs 492M 0 492M 0% /dev/shm /dev/sda1 ext4 485M 31M 429M 7% /boot /dev/sda2 ext4 20G 172M 19G 1% /home [root@localhost ~]# dd if=/dev/zero of=/dev/sda1 bs=512 count=8 8+0 records in 8+0 records out 4096 bytes (4.1 kB) copied, 0.00857931 s, 477 kB/s [root@localhost ~]# 出现grub> 进入营救模式 切换根:
=== [root@localhost ~]# mkfs.ext4 /dev/sdb1 [root@localhost ~]# mkfs.ext4 /dev/sdb2 [root@localhost ~]# mkdir /linux-1 [root@localhost ~]# mkdir /windows-1 [root@localhost ~]# mount -o ro /dev/sdb1 /linux-1 [root@localhost ~]# mount /dev/sdb2 /windows-1 [root@localhost ~]# df -Th Filesystem Type Size Used Avail Use% Mounted on /dev/sda5 ext4 58G 1.8G 53G 4% / tmpfs tmpfs 492M 0 492M 0% /dev/shm /dev/sda1 ext4 485M 31M 429M 7% /boot /dev/sda2 ext4 20G 172M 19G 1% /home /dev/sdb1 ext4 1020M 34M 935M 4% /linux-1 /dev/sdb2 ext4 2.0G 68M 1.9G 4% /windows-1 [root@localhost ~]#
[root@teacher proc]# cat /proc/mounts rootfs / rootfs rw 0 0 proc /proc proc rw,nosuid,nodev,noexec,relatime 0 0 sysfs /sys sysfs rw,nosuid,nodev,noexec,relatime 0 0 devtmpfs /dev devtmpfs rw,nosuid,relatime,size=1957800k,nr_inodes=178887,mode=755 0 0 devpts /dev/pts devpts rw,relatime,gid=5,mode=620,ptmxmode=000 0 0 tmpfs /dev/shm tmpfs rw,nosuid,nodev,relatime 0 0 /dev/sda3 / ext4 rw,relatime,barrier=1,data=ordered 0 0 /proc/bus/usb /proc/bus/usb usbfs rw,relatime 0 0 /dev/sda1 /boot ext4 rw,relatime,barrier=1,data=ordered 0 0 none /proc/sys/fs/binfmt_misc binfmt_misc rw,relatime 0 0 vmware-vmblock /var/run/vmblock-fuse fuse.vmware-vmblock rw,nosuid,nodev,relatime,user_id=0,group_id=0,default_permissions,allow_other 0 0 /dev/loop0 /iso-hou iso9660 ro,relatime 0 0 gvfs-fuse-daemon /root/.gvfs fuse.gvfs-fuse-daemon rw,nosuid,nodev,relatime,user_id=0,group_id=0 0 0
[root@localhost ~]# umount /dev/sdb1 可以接磁盘名 [root@localhost ~]# df -Th Filesystem Type Size Used Avail Use% Mounted on /dev/sda5 ext4 58G 1.8G 53G 4% / tmpfs tmpfs 492M 0 492M 0% /dev/shm /dev/sda1 ext4 485M 31M 429M 7% /boot /dev/sda2 ext4 20G 172M 19G 1% /home /dev/sdb2 ext4 2.0G 68M 1.9G 4% /windows-1 [root@localhost ~]# umount /windows-1/ 也可以接挂载点,都能卸载 [root@localhost ~]# df -TH Filesystem Type Size Used Avail Use% Mounted on /dev/sda5 ext4 62G 1.9G 57G 4% / tmpfs tmpfs 516M 0 516M 0% /dev/shm /dev/sda1 ext4 508M 32M 450M 7% /boot /dev/sda2 ext4 21G 181M 20G 1% /home [root@localhost ~]# 查看那个程序正在使用某个软件lsof fuser
buffer---》缓冲器---》内存往磁盘写数据的一个临时存放数据的空间 cached---》高速缓存--》当内存从磁盘读数据的时候,经常使用的数据存放再此
当交换分区开始使用的时候,说明你的物理内存不够使用了,如何处理? 可以kill掉一些进程
[root@localhost ~]# mkswap /dev/sdb5 Setting up swapspace version 1, size = 2104476 KiB no label, UUID=510684f2-b0c9-4951-8e09-6309ec1dc1b0 [root@localhost ~]# free -m total used free shared buffers cached Mem: 982 140 842 0 12 66 -/+ buffers/cache: 61 921 Swap: 1999 0 1999 [root@localhost ~]# [root@localhost ~]# swapon /dev/sdb5 不swapon加载swap的话看不到更新 [root@localhost ~]# free -m total used free shared buffers cached Mem: 982 141 840 0 12 66 -/+ buffers/cache: 62 920 Swap: 4055 0 4055 [root@localhost ~]# == [root@localhost ~]# cat /proc/swaps 查看交换分区的组成 Filename Type Size Used Priority /dev/sda3 partition 2047992 0 -1 /dev/sdb5 partition 2104472 0 -2 [root@localhost ~]# swapoff /dev/sdb5 [root@localhost ~]# free -m total used free shared buffers cached Mem: 982 140 841 0 12 66 -/+ buffers/cache: 61 921 Swap: 1999 0 1999 [root@localhost ~]# cat /proc/swaps 相当于swapon -s Filename Type Size Used Priority /dev/sda3 partition 2047992 0 -1 [root@localhost ~]#