查看“Linux命令”的源代码

== ssh ==
=== pem登入方式 ===
<source lang="shell">
# server端 设置 authorized_keys
# 确保 authorized_keys 权限600
# 把public key 存放在这个文件下
vi /home/sdn/.ssh/authorized_keys 

# 在client端，使用pem登入
ssh sdn@80.8.8.21 -i key-qingwyan2.pem

# 可以不用加 -i参数登入
ssh-add key-qingwyan2.pem
</source>
=== 免密登入 ===
<source lang="shell">
# ~/.ssh 目录下有如下文件
$ ls
authorized_keys  id_rsa  id_rsa.pub  known_hosts
# authorized_keys 权限必须600， 将client公有密匙（id_rsa.pub）copy到server同用户名的~/.ssh/authorized_keys里面，就能免密登入
</source>

=== debug ===
==== server端 ====
<source lang="shell">
# vi /etc/ssh/sshd_conf
LogLevel DEBUG3
# restart sshd
service sshd restart
# 查看log
tail -f /var/log/secure
</source>
==== client端 ====
<source lang="shell">
# -v debug1级别
# -vvv debug3级别
ssh -vvv sdn@80.8.8.21 -i key-qingwyan2.pem
</source>

== cmd ==
=== sshpass ===
<source lang="shell">
# 第一次必须ssh登入一次
sshpass -p cisco123 ssh root@192.168.125.186
</source>

== awk ==
=== 打印第一行第二列 ===
<source lang="shell">
ps -ef | grep sshd | head -n1 | awk {'print $2'}
# example
[qingwyan@localhost smartphy114]$ ps -ef | grep sshd
root      1405     1  0 Nov23 ?        00:00:00 /usr/sbin/sshd -D
root     13092  1405  0 19:49 ?        00:00:00 sshd: qingwyan [priv]
qingwyan 13108 13092  0 19:49 ?        00:00:00 sshd: qingwyan@notty
qingwyan 16602 32280  0 21:07 pts/5    00:00:00 grep --color=auto sshd
root     20010  1405  0 Nov28 ?        00:00:02 sshd: root@pts/19

[qingwyan@localhost smartphy114]$ ps -ef | grep sshd | head -n1 | awk {'print $2'}
1405
</source>

== sed ==
=== 替换文本里所有符合条件字符 ===
<source lang="shell">
sed -i 's/原来字符/替换字符/g' "替换的文件名"
</source>

== 用户管理 ==
=== 添加sudo权限用户 ===
<source lang="shell">
adduser username
passwd username
usermod -aG wheel username

# 修改文件 /etc/sudoers
## Allow root to run any commands anywhere
root    ALL=(ALL)     ALL
qingwyan  ALL=(ALL)     ALL
</source>

[[category: linux]]