How to view and modify ip addresses and open ports in CentOS

You know, you get used to ipconfig in windows. it is a lot of trouble to view the IP address in CentOS. The information collected today focuses on solving the IP port problem: view IPifconfigeth0 → view the IP address, but the output information is more ifconfig | grepBcast → the output information should be clear. modify the IP address and edit/etc/sysconfig/. you know, I am used to ipconfig in windows, and it is a lot of trouble to view IP addresses in CentOS;
The information collected today focuses on IP port problems:

View IP
Ifconfig eth0 → view the IP address, but the output information is more
Ifconfig | grep 'bcast' → the output information should be much clearer.

Modify IP address and take effect
Edit/etc/sysconfig/network-scripts/ifcfg-eth0 and follow the settings below
DEVICE = eth0
BOOTPROTO = static
HWADDR =
ONBOOT = yes
TYPE = Ethernet
IPADDR = <你的ip>
NETMASK = 255.255.255.0

The MAC address can be viewed using the ifconfig eth0 command.

After setting, restart the network service:
Service network restart

After the CentOS system is installed, only port 22 is enabled by default. to open other ports, open the required ports.
Vi/etc/sysconfig/ Iptables

Then add
-A RH-Firewall-1-INPUT-m state -- state NEW-m tcp-p tcp -- dport3001-j ACCEPT
-A RH-Firewall-1-INPUT-m state -- state NEW-m tcp-p tcp -- dport3001-j ACCEPT

Finally, the CentOS system needs to restart the service.
/Sbin/service iptables restart
/Sbin/service iptables restart

Check whether the port is open
/Sbin/iptables-L-n
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