CentOS commands for viewing IP addresses, modifying IP addresses on ports, and activating ports

You know that ipconfig is used to 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 IPifconfigeth0 & rarr; check the IP address, but the output information is more ifconfig | grep & #39; Bcast & #39; & rarr; the output information should be clear and the IP address should be modified.

You know, you get 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:

1. View IP
   Ifconfig eth0 → view the IP address, but the output information is more
   Ifconfig | grep 'bcast' → the output information should be much clearer.
2. 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
3. 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 the Java code to the CentOS system.
-A RH-Firewall-1-INPUT-m state -- state NEW-m tcp-p tcp -- dport 3001-j ACCEPT
-A RH-Firewall-1-INPUT-m state -- state NEW-m tcp-p tcp -- dport 3001-j ACCEPT

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

Check whether Java code is enabled on the port

/Sbin/iptables-L-n