More catalog knowledge http://blog.51cto.com/yangrong/1288072

/etc/fstab　　

Machine automatically mounts partition / disk, specifies which partition / device and where to mount

 1 [root@oldboy ~]# cat /etc/fstab
 2 
 3 #
 4 # /etc/fstab
 5 # Created by anaconda on Sun Aug 12 17:26:53 2018
 6 #
 7 # Accessible filesystems, by reference, are maintained under '/dev/disk'
 8 # See man pages fstab(5), findfs(8), mount(8) and/or blkid(8) for more info
 9 #
10 UUID=c9b74b1a-41cd-4260-9444-6245ab833dd9 /                       ext4    defaults        1 1
11 UUID=8880df83-5bf8-40db-bf6f-bf878b7a7e2e /boot                   ext4    defaults        1 2
12 UUID=3144b92b-c079-4239-9a91-84111d2f1ac1 swap                    swap    defaults        0 0
13 tmpfs //To mount a device       /dev/shm //Mount point        tmpfs//file system typedefaults//Hang on options0//Backup0//Whether to do self check after power on
14 devpts                  /dev/pts                devpts  gid=5,mode=620  0 0
15 sysfs                   /sys                    sysfs   defaults        0 0
16 proc                    /proc                   proc    defaults        0 0

/etc/resolv.conf

DNS temporary profile

 1 [root@oldboy ~]#  cat /etc/resolv.conf 
 2 ; generated by /sbin/dhclient-script
 3 search localdomain
 4 nameserver 192.168.182.2
 5 [root@oldboy ~]# vi /etc/resolv.conf 
 6 ; generated by /sbin/dhclient-script
 7 search localdomain
 8 nameserver 192.168.182.2
 9 nameserver 8.8.8.8
10 ~                                                                               
11 ~                                                                                                                                                           
12 ~                                                                               
13 ~                                                                               
14 "/etc/resolv.conf" 4L, 100C written
15 [root@oldboy ~]#  cat /etc/resolv.conf 
16 ; generated by /sbin/dhclient-script
17 search localdomain
18 nameserver 192.168.182.2
19 nameserver 8.8.8.8

 /etc/hosts

Host name resolution file:

The corresponding relationship between ip address and domain name in hosts file

Effect:

• Used by developers, products, testers, etc. to test products through official domain names
• Domain name (internal DNS) can be used for calls between servers to facilitate migration

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

 /etc/sysconfig/nework

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

Modify host name

• vim  /etc/sysconfig/network
• sed -i  's#HOSTNAME=study#HOSTNAME=centos#g'  /etc/sysconfig/network

/etc/rc.local

The file stored by the bootstrap command (chkconfig is often used to manage the bootstrap of program services installed by yum/rmp)

/etc/inittab

Run level profile

/etc/issue

Login prompt profile

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

/var/log/messages

System information log file