Tset 7
1、Ubuntu系统网络配置总结（包括主机名、网卡名称、网卡配置）
~~~bash
修改主机名
root@ubuntu1804:~# hostnamectl set-hostname ubuntu1804.magedu.org
root@ubuntu1804:~# cat /etc/hostname
ubuntu1804.magedu.org
root@ubuntu1804:~# hostname
ubuntu1804.magedu.org
网卡名称
#修改配置文件为下面形式
root@ubuntu1804:~#vi /etc/default/grub
GRUB_CMDLINE_LINUX="net.ifnames=0"
#或者sed修改
root@ubuntu1804:~# sed -i.bak '/^GRUB_CMDLINE_LINUX=/s#"$#net.ifnames=0"#'
/etc/default/grub
#生效新的grub.cfg文件
root@ubuntu1804:~# grub-mkconfig -o /boot/grub/grub.cfg
#或者
root@ubuntu1804:~# update-grub
root@ubuntu1804:~# grep net.ifnames /boot/grub/grub.cfg
linux /vmlinuz-4.15.0-96-generic root=UUID=51517b88-7e2b-4d4a-8c14-
fe1a48ba153c ro net.ifnames=0
linux /vmlinuz-4.15.0-96-generic root=UUID=51517b88-7e2b-4d4a-
8c14-fe1a48ba153c ro net.ifnames=0
linux /vmlinuz-4.15.0-96-generic root=UUID=51517b88-7e2b-4d4a-
8c14-fe1a48ba153c ro recovery nomodeset net.ifnames=0
linux /vmlinuz-4.15.0-76-generic root=UUID=51517b88-7e2b-4d4a-
8c14-fe1a48ba153c ro net.ifnames=0
linux /vmlinuz-4.15.0-76-generic root=UUID=51517b88-7e2b-4d4a-
8c14-fe1a48ba153c ro recovery nomodeset net.ifnames=0
#重启生效
root@ubuntu1804:~# reboot
配置自动获取IP
root@ubuntu1804:~# cat /etc/netplan/01-netcfg.yaml
# This file describes the network interfaces available on your system
# For more information, see netplan(5).
network:
version: 2
renderer: networkd
ethernets:
eth0:
dhcp4: yes
静态的IP配置
[root07:19 PMubuntu /etc/netplan]#pwd
/etc/netplan
[root07:10 PMubuntu /etc/netplan]#cat 02-eth1.yaml
network:
version: 2
renderer: networkd
ethernets:
eth1:
addresses: [192.168.8.10/24,10.0.0.10/8]
gateway4: 10.0.0.2
nameservers:
search: [magedu.com, magedu.org]
addresses: [180.76.76.76, 8.8.8.8, 1.1.1.1]
修改网卡配置文件后需执行命令生效：
root@ubuntu1804:~#netplan apply
~~~
2、编写脚本实现登陆远程主机。（使用expect和shell脚本两种形式）。
~~~bash
expect方式
第一步：编写文件
[root@centos7 scripts]#vim expect
#!/usr/bin/expect
spawn ssh 10.0.0.18
expect {
"yes/no" { send "yes\n";exp_continue }
"password" { send "123456\n" }
}
interact
第二步:加执行权限执行脚本
[root@centos7 scripts]#chmod +x expect
[root@centos7 scripts]#./expect
spawn ssh 10.0.0.18
root@10.0.0.18's password:
Last login: Tue Jun 22 09:57:01 2021 from 10.0.0.17
[root@ ~]#hostname -I
10.0.0.18 10.0.0.118
=====================================================
shell方式
[root@centos7: script]#cat expect6.sh
#!/bin/bash
ip=$1
user=$2
password=$3
expect < ${nums[$next]} ));then
tmp=${nums[$next]}
nums[$next]=${nums[$j]}
nums[$j]=$tmp
fi
done
done
echo "after sort:${nums[*]}"
echo "the Min integer is ${nums[0]},the max integer is ${nums[$(( n-1 ))]}"
~~~
5、显示统计占用系统内存最多的进程，并排序。
~~~bash
ps -aux |sort -k4nr
ps aux --sort=-%mem
~~~
6、编写脚本，使用for和while分别实现192.168.0.0/24网段内，地址是否能够ping通，若ping通则输出"success!"，若ping不通则输出"fail!"
~~~bash
#由于使用的是10.0.0.0/24 网段，所以用10.0.0.0/24的测试
方法一
[root@centos7 scripts]#cat 39.sh
#!/bin/bash
net_ip=10.0.0.
for i in {1..255};do
{
if /bin/ping -c1 -W1 $net_ip$i >/dev/null ;then
echo "$net_ip$i is UP success! "
else
echo "$net_ip$i is DOWN fail! "
fi
}&
done
wait
方法二：
[root@centos7 scripts]#echo 10.0.0.{1..254} |tr -s " " "\n" > ip.txt
[root@centos7 scripts]#cat 40.sh
#!/bin/bash
while read ip ;do
{
ping -c1 -W1 $ip >/dev/null
[ $? -eq 0 ] && echo "$ip success" || echo "$ip fail"
}&
done