谈一谈Linux系统重要的子目录问题

 [root@oldboy ~]# cat /etc/fstab
#
# /etc/fstab
# Created by anaconda on Sun Aug 12 17:26:53 2018
#
# Accessible filesystems, by reference, are maintained under '/dev/disk'
# See man pages fstab(5), findfs(8), mount(8) and/or blkid(8) for more info
#
UUID=c9b74b1a-41cd-4260-9444-6245ab833dd9 /            ext4  defaults    1 1
UUID=8880df83-5bf8-40db-bf6f-bf878b7a7e2e /boot          ext4  defaults    1 2
UUID=3144b92b-c079-4239-9a91-84111d2f1ac1 swap          swap  defaults    0 0
tmpfs //要挂载设备    /dev/shm //挂载点    tmpfs//文件系统类型defaults//挂在选项0//是否备份0//是否做开机自检查
devpts         /dev/pts        devpts gid=5,mode=620 0 0
sysfs          /sys          sysfs  defaults    0 0
proc          /proc          proc  defaults    0 0

[root@oldboy ~]# cat /etc/resolv.conf 
; generated by /sbin/dhclient-script
search localdomain
nameserver 192.168.182.2
[root@oldboy ~]# vi /etc/resolv.conf 
; generated by /sbin/dhclient-script
search localdomain
nameserver 192.168.182.2
nameserver 8.8.8.8
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"/etc/resolv.conf" 4L, 100C written
[root@oldboy ~]# cat /etc/resolv.conf 
; generated by /sbin/dhclient-script
search localdomain
nameserver 192.168.182.2
nameserver 8.8.8.8

[root@oldboy ~]# cat /etc/hosts
127.0.0.1  localhost localhost.localdomain localhost4 localhost4.localdomain4
::1     localhost localhost.localdomain localhost6 localhost6.localdomain6

[root@study ~]# cat /etc/sysconfig/network
NETWORKING=yes
HOSTNAME=study　　//主机名

[root@study ~]# cat /etc/issue
CentOS release 6.7 (Final)
Kernel \r on an \m