运行SSH远程命令和grep一个字符串 [英] Running ssh remote command and grep for a string

问题描述

我想要写脚本，将远程运行一些SSH远程命令。所有我需要的是到grep命令执行的输出对某些特殊字符串这将意味着成功执行该命令。例如，当我运行这样的：

I want to write script that will remotely run some ssh remote commands. All I need is to grep output of executed command for some special string which will mean that command executed successfully. For example when I run this:

ssh user@host "sudo /etc/init.d/haproxy stop"

我得到的输出：

Stopping haproxy: [  OK  ]

所有我需要的是找到OK的字符串，以确保成功执行该命令。我怎样才能做到这一点？

All I need is to find "OK" string to ensure that command executed successfully. How can I do this?

推荐答案

添加的grep ，并检查退出状态：

Add grep and check exit status:

ssh user@host "sudo /etc/init.d/haproxy stop | grep -Fq '[  OK  ]'"
if [ "$#" -eq 0 ]; then
    echo "Command ran successfully."
else
    echo "Command failed."
fi

您还可以将的grep 之外。

ssh user@host "sudo /etc/init.d/haproxy stop" | grep -Fq '[  OK  ]'

其他的方法来检查退出状态：

Other ways to check exit status:

command && { echo "Command ran successfully."; }
command || { echo "Command failed."; }
if command; then echo "Command ran successfully."; else echo "Command failed."; fi

您也可以捕获输出，并与情况或 [[]] 比较：

You can also capture output and compare it with case or with [[ ]]:

OUTPUT=$(exec ssh user@host "sudo /etc/init.d/haproxy stop")
case "$OUTPUT" in
*'[  OK  ]'*)
    echo "Command ran successfully."
    ;;
*)
    echo "Command failed."
esac

if [[ $OUTPUT == *'[  OK  ]'* ]]; then
    echo "Command ran successfully."
else
    echo "Command failed."
fi

和可以嵌入 $（EXEC SSH用户@主机命令/etc/init.d/haproxy停）直接作为一名前pression代替如果想通过输出变量。

And you can embed $(exec ssh user@host "sudo /etc/init.d/haproxy stop") directly as an expression instead of passing output to a variable if wanted.

如果 /etc/init.d/haproxy停止将消息发送到stderr而不是，只是把它重定向到stdout，所以你可以捕捉它：

If /etc/init.d/haproxy stop sends messages to stderr instead, just redirect it to stdout so you can capture it:

sudo /etc/init.d/haproxy stop 2>&1

这篇关于运行SSH远程命令和grep一个字符串的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！