01 - Linux CentOS网络配置

02 - Linux查看端口状态

检测本机8080端口状态：netstat –apn | grep 8080

检测192.168.0.1主机的8080端口状态：telnet 192.168.0.1 8080 或nmap -sS -P0 -n -p 22 192.168.0.1

检测192.168.0.1主机的1到1024端口状态：nc -z 192.168.0.1 1-1024

# nmap -sS -P0 -n -p 22 10.140.0.135Starting Nmap 6.40 ( http://nmap.org ) at 2016-11-09 10:42 CSTNmap scan report for 10.140.0.135Host is up (0.00040s latency).PORT STATE SERVICE22/tcp open sshMAC Address: 08:00:27:3F:19:79 (Cadmus Computer Systems)Nmap done: 1 IP address (1 host up) scanned in 0.07 seconds # nmap -sS -P0 -n -p 80 10.140.0.135Starting Nmap 6.40 ( http://nmap.org ) at 2016-11-09 10:50 CSTNmap scan report for 10.140.0.135Host is up (0.00046s latency).PORT STATE SERVICE80/tcp closed httpMAC Address: 08:00:27:3F:19:79 (Cadmus Computer Systems)Nmap done: 1 IP address (1 host up) scanned in 0.06 seconds

03 - Linux命令行设置CentOS计算机名称、hosts及网卡地址

$ echo "anliven" > /etc/hostname$ echo -e "192.168.16.166 master\n192.168.16.167 slave01\n192.168.16.168 slave02" >> /etc/hosts$ sed -i '/IPADDR/s/192.168.16.200/192.168.16.166/' /etc/sysconfig/network-scripts/ifcfg-enp0s8$ reboot

04 - Linux CentOS7关闭SELinux

• 永久方法：修改/etc/selinux/config文件中设置SELINUX=disabled ，然后重启。

# getenforceEnforcing# sed -i '/SELINUX/s/enforcing/disabled/' /etc/selinux/config# reboot

• 临时方法：执行setenforce 0命令设置SELinux成为permissive模式

sudo systemctl status firewalld.servicesudo systemctl stop firewalld.service          sudo systemctl disable firewalld.service

05 - Ubuntu安装ssh并允许root登录

1. Install openssh-server

apt-get updateapt-get install openssh-server

1. Change ssh configuration

root@anliven:~# vim /etc/ssh/sshd_config root@anliven:~# root@anliven:~# cat /etc/ssh/sshd_config |grep RootLogin#PermitRootLogin without-passwordPermitRootLogin yes# the setting of "PermitRootLogin without-password".root@anliven:~# root@anliven:~# /etc/init.d/ssh restartssh stop/waitingssh start/running, process 3782root@anliven:~#

1. Check ssh status

root@anliven:~# lsof -i:22COMMAND  PID USER   FD   TYPE DEVICE SIZE/OFF NODE NAMEsshd    3630 root    3u  IPv4  19611      0t0  TCP *:ssh (LISTEN)sshd    3630 root    4u  IPv6  19613      0t0  TCP *:ssh (LISTEN)root@anliven:~# root@anliven:~# ps -ef |grep sshroot      3630     1  0 13:43 ?        00:00:00 /usr/sbin/sshd -D    root      3750  3732  0 13:46 pts/1    00:00:00 grep --color=auto sshroot@anliven:~#

06 - Linux常用网络软件包

• inetuils-ping --- ping
• net-tools --- ifconfig/route/netstat/......
• iproute --- ip
• traceroute
• bind-utils --- nslookup/dig/host/......
• bridge-utils --- brctl
• nmap
• tcpdump
• wireshark
• curl
• wget
  ......

07 - Linux设置ssh免密码认证

示例：slave01和slave02两个主机ssh免密码相互登录

### 设置slave01 node[hadoop@slave01 ~]$ ssh-keygen[hadoop@slave01 ~]$ [hadoop@slave01 ~]$ cd .ssh[hadoop@slave01 .ssh]$ ssh-copy-id -i hadoop@slave01[hadoop@slave01 .ssh]$ ssh-copy-id -i hadoop@slave02[hadoop@slave01 .ssh]$ [hadoop@slave01 .ssh]$ ll -atotal 20drwx------  2 hadoop hadoop   76 Mar  7 23:34 .drwx------. 6 hadoop hadoop 4096 Mar  7 23:30 ..-rw-------  1 hadoop hadoop 1187 Mar  7 23:34 authorized_keys-rw-------  1 hadoop hadoop 1675 Mar  7 23:33 id_rsa-rw-r--r--  1 hadoop hadoop  396 Mar  7 23:33 id_rsa.pub-rw-r--r--  1 hadoop hadoop  551 Mar  7 23:34 known_hosts[hadoop@slave01 .ssh]$ ### 设置slave02 node[hadoop@slave02 ~]$ ssh-keygen[hadoop@slave02 ~]$ [hadoop@slave02 ~]$ cd .ssh[hadoop@slave02 .ssh]$ ssh-copy-id -i hadoop@slave01[hadoop@slave02 .ssh]$ ssh-copy-id -i hadoop@slave02[hadoop@slave02 .ssh]$ [hadoop@slave02 .ssh]$ ll -atotal 20drwx------  2 hadoop hadoop   76 Mar  7 23:35 .drwx------. 6 hadoop hadoop 4096 Mar  7 23:30 ..-rw-------  1 hadoop hadoop 1187 Mar  7 23:35 authorized_keys-rw-------  1 hadoop hadoop 1675 Mar  7 23:33 id_rsa-rw-r--r--  1 hadoop hadoop  396 Mar  7 23:33 id_rsa.pub-rw-r--r--  1 hadoop hadoop  551 Mar  7 23:35 known_hosts[hadoop@slave01 .ssh]$

08 - Linux设置路由并指定metric值

• 默认路由：route add default gw 10.0.2.2 metric 1
• 指定路由：route add 192.168.0.0 mask 255.255.0.0 192.168.16.1 metric 10

09 - Linux虚拟机出现多个默认路由，导致部分网络连接异常

# route -nKernel IP routing tableDestination     Gateway         Genmask         Flags Metric Ref    Use Iface0.0.0.0         192.168.16.1    0.0.0.0         UG    100    0        0 enp0s30.0.0.0         10.0.3.2        0.0.0.0         UG    101    0        0 enp0s8......

处理方法：更改网关192.168.16.1的路由设置。

• CentOS7：应用程序---》系统工具---》设置---》网络---》以太网（enp0s3），点击右下角的设置按钮---》IPv4---》选择“仅对此网络上的资源使用此连接”---》应用。
• Ubuntu1604：系统设置---》网络---》有线，选择对应网卡---》选项---》IPv4设置---》路由---》选择“仅将此连接用于相对应的网络上的资源”---》确定。

# route -n......192.168.16.0    0.0.0.0         255.255.255.0   U     100    0        0 enp0s3......

10 - xxx