Modify the Host Name of centos (Do not spray), and change the Host Name of centos

Modify the Host Name of centos (Do not spray), and change the Host Name of centos
1. Temporarily modify the Host Name

Show Host Name:
Spark @ master :~ $ Hostname
Master

Modify host name:
Spark @ master :~ $ Sudo hostname hadoop
Spark @ master :~ $ Hostname
Hadoop

PS: the above changes are only temporary changes, and the changes are restored after the restart.

2. Change the host name permanently.

Permanent modification on redhat/centos

[Root @ localhost ~] # Cat/etc/sysconfig/network
NETWORKING = yes
HOSTNAME = localhost. localdomain
GATEWAY = 192.168.10.1

Modify the HOSTNAME of the network. The host name is located at the beginning and the domain name is located at the end. The host name is ignored.

[Root @ localhost ~] # Vi/etc/sysconfig/network

NETWORKING = yes
NETWORKING_IPV6 = no
HOSTNAME = master

This is a permanent modification and takes effect after restart. I do not know how to take effect immediately.

To take effect immediately, you can use the first method at the same time.

Another change is:

/Etc/hosts

127.0.0.1 localhost. localdomain

The part after 127.0.0.1.

Modify on deb/ubuntu:

Hostname
Localhost. localdomain

Sudo vi/etc/hostname

Enter hostname as master in/etc/hostname

Spark @ localhost :~ $ Cat/etc/hostname
Localhost

After the restart, the prompt is changed.

Spark @ master :~ $

If you do not want to restart, use the hostname command.

3. Other modification methods

Use sysctl to modify kernel. hostname

View:

Spark @ master :~ $ Sysctl kernel. hostname
Kernel. hostname = master

Modify:

Spark @ master :~ $ Sudo sysctl kernel. hostname = hadoop
Kernel. hostname = hadoop

Re-open the shell and change it to the following hostname: hadoop

Spark @ master :~ $