Question

如果我们的服务器上的负载过高，我正在尝试通过脚本向我发送通知。我找到了一个很好的但是当我运行时它给了我和错误，我看不出原因。

运行以下代码会出错：

第13行：意外标记“fi”附近的语法错误

我认为我必须正确布置。谢谢！

#!/bin/bash

THR=10
MAIL="address@domain.com"

VAR=`uptime|awk -F, '{print $4}'|awk '{print $3}'`
OUT=`echo "$VAR $THR" | awk '{if ($1 > $2) print "yes"; else print "no"}'`
if [ "$VAR" == "" ]
then
  # it's within the first 24 hours of uptime
  VAR=`uptime|awk -F, '{print $3}'|awk '{print $3}'`
  OUT=`echo "$VAR $THR" | awk '{if ($1 > $2) print "yes"; else print "no"}'`
fi
if [ "$OUT" == "yes" ]
then
  echo "The current load $VAR is greater than the threshold $THR" | mail $MAIL
  -s "Server Load Alert"
  echo "Alert generated because $VAR is greater than $THR"
else
  echo "No alert as $VAR > $THR"
fi
echo "load = $VAR"

Answer 1

对不起，没有冒犯，但你的bash风格很糟糕！

这是一个更好的版本：

#!/bin/bash

thr=10
mail="address@domain.com"

read var _ < /proc/loadavg

if (( $(bc -l <<< "$var>$thr") )); then
    echo "The current load $var is greater than the threshold $thr" | mail "$mail" -s "Server Load Alert"
    echo "Alert generated because $var is greater than $thr"
else
    echo "No alert as $var <= $thr"
fi
echo "load = $var"

更改如下：

使用小写变量名称，因为大写变量名称被认为是糟糕的bash实践。
不要使用数百万个管道，子shell和uptime解析命令awk的输出，因为它效率低，直接从文件/proc/loadavg获取相同的信息，一个read内置。
请勿使用awk来测试不等式，使用bc，效率更高（并且根本不需要变量$OUT。）
没有反击！改为使用$(...)构造（更容易阅读，嵌套和更好的bash练习）。

我没有测试过脚本，只是在我阅读时纠正了你的脚本。请告诉我它是否适合你。

Answer 2

#!/bin/bash

THR=10
MAIL="address@domain.com"

VAR=`uptime|awk -F, '{print $4}'|awk '{print $3}'`
OUT=`echo "$VAR $THR" | awk '{if ($1 > $2) print "yes"; else print "no"}'`
if [ "$VAR" == "" ]
then
# it's within the first 24 hours of uptime
VAR=`uptime|awk -F, '{print $3}'|awk '{print $3}'`
OUT=`echo "$VAR $THR" | awk '{if ($1 > $2) print "yes"; else print "no"}'`
fi
if [ "$OUT" == "yes" ]
then
echo "The current load $VAR is greater than the threshold $THR" | mail $MAIL -s "Server Load Alert"
echo "Alert generated because $VAR is greater than $THR"
else
echo "No alert as $VAR > $THR"
fi
echo "load = $VAR"

这对我有用。我更改了“mail $ MAIL”和-s“Server Load Alert”保持在同一行。

Bash脚本错误。意外令牌附近的语法错误

2 个答案: