df,du,swap小命令
df命令:
df -l :仅显示本地文件系统的相关系统 [root@localhost local]# df -l /dev/sdb2 Filesystem 1K-blocks Used Available Use% Mounted on - 494788 260 494528 1% /dev [root@localhost local]# df -l Filesystem 1K-blocks Used Available Use% Mounted on /dev/sda2 121418860 2719280 112525116 3% / tmpfs 506144 72 506072 1% /dev/shm /dev/sda1 289293 28485 245448 11% /boot [root@localhost local]#
-h :单位换算 [root@localhost local]# df -h /dev/sdb2 Filesystem Size Used Avail Use% Mounted on - 484M 260K 483M 1% /dev [root@localhost local]#
-i :显示inode的使用情况而非磁盘块的 [root@localhost local]# df -i /dev/sdb2 Filesystem Inodes IUsed IFree IUse% Mounted on - 123697 756 122941 1% /dev [root@localhost local]#
du 用于评估文件大小 -s :统计整个目录及内部所有文件总体大小; [root@localhost local]# du -s /etc/ 39556 /etc/ [root@localhost local]#
-h:human-readable [root@localhost local]# du -sh /etc/ 39M /etc/ [root@localhost local]#
mkswap free命令:查看内存的使用状况 free -m 兆显示 -g G显示 [root@localhost local]# free total used free shared buffers cached Mem: 1012292 623920 388372 1360 26996 395064 -/+ buffers/cache: 201860 810432 Swap: 2031612 0 2031612 [root@localhost local]# free -m total used free shared buffers cached Mem: 988 609 379 1 26 385 -/+ buffers/cache: 197 791 Swap: 1983 0 1983 [root@localhost local]# free -g total(总体) used(已用) free(空闲) shared(共享) buffers(缓冲) cached(缓存) Mem: 0 0 0 0 0 0 -/+ buffers/cache:() 0 0 Swap: 1 0 1 [root@localhost local]# 如何启用交换分区 swapon /dev/sda6(创建好的swap) -a:启用/etc/fstab文件中定义的所有交换分区
禁用交换分区 swapoff device
文件系统相关的配置文件:/etc/fstab [root@localhost local]# cat /etc/fstab
# 1. /etc/fstab 1. Created by anaconda on Sat Apr 4 08:45:23 2015 1. 1. Accessible filesystems, by reference, are maintained under '/dev/disk' 1. See man pages fstab(5), findfs(8), mount(8) and/or blkid(8) for more info 1. UUID=4fb479dc-0364-41ac-a12d-841210d879a4 / ext4 defaults 1 1 UUID=30d2724b-a9be-4e32-8b9a-cf731a92173a /boot ext4 defaults 1 2 UUID=7568de25-a229-43cb-952a-ca5fd83bbdcc swap swap defaults 0 0 tmpfs /dev/shm tmpfs defaults 0 0 devpts /dev/pts devpts gid=5,mode=620 0 0 sysfs /sys sysfs defaults 0 0 proc /proc proc defaults 0 0 [root@localhost local]# 定义开机可自动挂载的文件系统,每行一个: /etc/fstab 6个列/字段 1,挂载的设备 设备文件 卷标 uuid 伪文件系统:如sysfs,proc,tmpfs等 2, 挂载点 swap的挂载点仍为swap 3,文件系统类型 4, 挂载选项 defaults表示使用默认挂载选项,多个挂载选项间使用逗号分隔:如defaults,alc,noatime 5,转储频率,多久备份一次 0:不备份 1:每天备份 2:每隔一天备份 6,自检次序,开机对文件自检 0:不自检 1:首先自检,通常根文件系统可首先自检 2:次级自检 .... 一般来讲,除了根,其他文件开机不自检 示例:将/dev/sdb2 挂载到/tmp/1mark vim /etc/fstab /dev/sdb2 /tmp/1mark ext4 defaults,noatime 0 0 wq保存退出
mount -a 当前系统自动挂载 [root@localhost local]# mount /dev/sda2 on / type ext4 (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,rootcontext="system_u:object_r:tmpfs_t:s0") /dev/sda1 on /boot type ext4 (rw) none on /proc/sys/fs/binfmt_misc type binfmt_misc (rw) vmware-vmblock on /var/run/vmblock-fuse type fuse.vmware-vmblock (rw,nosuid,nodev,default_permissions,allow_other) [root@localhost local]# mount -a [root@localhost local]# mount /dev/sda2 on / type ext4 (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,rootcontext="system_u:object_r:tmpfs_t:s0") /dev/sda1 on /boot type ext4 (rw) none on /proc/sys/fs/binfmt_misc type binfmt_misc (rw) vmware-vmblock on /var/run/vmblock-fuse type fuse.vmware-vmblock (rw,nosuid,nodev,default_permissions,allow_other) /dev/sdb2 on /tmp/1mark type ext4 (rw,noatime) [root@localhost local]#