ubuntu换镜像\修改历史记录\设置防火墙\删除冗余软件

1.ubuntu的国内镜像源更新

首先拷贝一份镜像源文件

sudo cp /etc/apt/sources.list /etc/apt/sources.list_backup

然后开始编辑这个新的文件

sudo vim /etc/apt/sources.list

18版本

deb http://mirrors.aliyun.com/ubuntu/ bionic main restricted universe multiverse
deb http://mirrors.aliyun.com/ubuntu/ bionic-security main restricted universe multiverse
deb http://mirrors.aliyun.com/ubuntu/ bionic-updates main restricted universe multiverse
deb http://mirrors.aliyun.com/ubuntu/ bionic-proposed main restricted universe multiverse
deb http://mirrors.aliyun.com/ubuntu/ bionic-backports main restricted universe multiverse
deb-src http://mirrors.aliyun.com/ubuntu/ bionic main restricted universe multiverse
deb-src http://mirrors.aliyun.com/ubuntu/ bionic-security main restricted universe multiverse
deb-src http://mirrors.aliyun.com/ubuntu/ bionic-updates main restricted universe multiverse
deb-src http://mirrors.aliyun.com/ubuntu/ bionic-proposed main restricted universe multiverse
deb-src http://mirrors.aliyun.com/ubuntu/ bionic-backports main restricted universe multiverse    

20版本

deb http://mirrors.aliyun.com/ubuntu/ focal main restricted universe multiverse
deb-src http://mirrors.aliyun.com/ubuntu/ focal main restricted universe multiverse
deb http://mirrors.aliyun.com/ubuntu/ focal-security main restricted universe multiverse
deb-src http://mirrors.aliyun.com/ubuntu/ focal-security main restricted universe multiverse
deb http://mirrors.aliyun.com/ubuntu/ focal-updates main restricted universe multiverse
deb-src http://mirrors.aliyun.com/ubuntu/ focal-updates main restricted universe multiverse
deb http://mirrors.aliyun.com/ubuntu/ focal-proposed main restricted universe multiverse
deb-src http://mirrors.aliyun.com/ubuntu/ focal-proposed main restricted universe multiverse
deb http://mirrors.aliyun.com/ubuntu/ focal-backports main restricted universe multiverse
deb-src http://mirrors.aliyun.com/ubuntu/ focal-backports main restricted universe multiverse

22版本

deb http://mirrors.aliyun.com/ubuntu/ jammy main restricted universe multiverse
deb-src http://mirrors.aliyun.com/ubuntu/ jammy main restricted universe multiverse
deb http://mirrors.aliyun.com/ubuntu/ jammy-security main restricted universe multiverse
deb-src http://mirrors.aliyun.com/ubuntu/ jammy-security main restricted universe multiverse
deb http://mirrors.aliyun.com/ubuntu/ jammy-updates main restricted universe multiverse
deb-src http://mirrors.aliyun.com/ubuntu/ jammy-updates main restricted universe multiverse
deb http://mirrors.aliyun.com/ubuntu/ jammy-proposed main restricted universe multiverse
deb-src http://mirrors.aliyun.com/ubuntu/ jammy-proposed main restricted universe multiverse
deb http://mirrors.aliyun.com/ubuntu/ jammy-backports main restricted universe multiverse
deb-src http://mirrors.aliyun.com/ubuntu/ jammy-backports main restricted universe multiverse

2.ubuntu设置history保存更久的历史记录,并且记录历史记录的行数

sudo vim /etc/profile.d/history_conf.sh
写入内容
export HISTFILE="$HOME/.bash_history_new"  # 指定命令写入文件(默认~/.bash_history)
export HISTSIZE=10000  # history输出记录数
export HISTFILESIZE=100000  # HISTFILE文件记录数
export HISTCONTOL=erasedups   # ignoredups 不记录“重复”的命令；连续且相同 方为“重复” ；
export PROMPT_COMMAND="history -a"  # 设置每条命令执行完立即写入HISTFILE(默认等待退出会话写入)
export HISTTIMEFORMAT="`whoami` %F %T "  # 设置命令执行时间格式，记录文件增加时间戳(`whoami`用户信息)
shopt -s histappend  # 防止会话退出时覆盖其他会话写到HISTFILE的内容；
把上述命令加入bashrc和profile中

3.ubuntu彻底删除软件和环境变量

ubuntu彻底删除软件和环境变量/配置
sudo apt-get purge 名字

sudo apt-get autoremove

sudo apt-get autoclean

dpkg -l |grep ^rc|awk '{print $2}' |sudo xargs dpkg -P 名字

sudo apt-get update

4.ubuntu的防火墙

sudo apt-get install ufw
sudo ufw status	
sudo ufw status verbose
拒绝其他主机连接
sudo ufw enablesudo ufw default deny incoming
# 默认允许该主机所有对外连接请求
sudo ufw default allow outgoing
# 允许 ssh 服务（服务名）
sudo ufw allow ssh
# 允许 ssh 服务（端口号）
sudo ufw allow 22
# 允许特定协议的端口访问
sudo ufw allow 21/tcp
# 允许特定端口范围
sudo ufw allow 6000:6007/tcp
sudo ufw allow 6000:6007/udp