Getting Started with CentOS learn notes-network and firewalls

First, configure the network, firewall, etc.

Setup command

Second, view the network

The ifconfig, route, and IP commands of the CentOS application http://www.linuxidc.com/Linux/2013-05/83956.htm

Ifconfig

Restart Network

/ect/init.d/network restart

or Ifup ethx (0,1,2), etc.

View network configuration Files

Cat (vi)/etc/sysconfig/network-script/ifcfg-eth0;

If Onboot=no please change to Yes, or restart cannot be automatically connected need to manually re-enable the NIC

Third, switch graphics or text mode

Modify the/etc/inittab file, which has a line id:3:initdefault, meaning that the boot is entered by default
Run Level 3 (multi-user text interface), change it to Id:5:initdefault, the default entry
Run Level 5 (multi-user graphical interface).

Iv. Viewing system versions

See if it's X86 or X64 system: uname-m

x86_64

View kernel and system version: Uname-r

2.6.32-504.el6.x86_64

View kernel and system version details: uanme-a

Linux model 2.6.32-504.el6.x86_64 #1 SMP Wed Oct 04:27:16 UTC x86_64 x86_64 x86_64 gnu/linux

To view the system version number: Cat/etc/redhat-release will list system types such as: CentOS release 6.6 (Final)

Five, SSH connection tool

securecrt Background color change:

Options-session Options-terminal-emulation-right terminal select Linux (white on black) or other personal favorite

Server-side to see if SSH is turned on

Netstat-lntup|grep 22

SECURECRT using configuration details Tutorial http://www.linuxidc.com/Linux/2015-01/112172.htm

How do I log on to a Linux server with a public key on SECURECRT? Http://www.linuxidc.com/Linux/2014-11/109973.htm

securecrt Details : please click here
securecrt : please click here.

Vi. Viewing the installed Grouplist

View already installed: Yum grouplist

Update all installed: Yum upgrade a bit like Windows patching and software upgrade feel

Getting Started with CentOS learn notes-network and firewalls