Question

文件1是/etc/hosts文件，输出低于

10.0.0.1     router1
10.0.0.2     router2
10.0.0.3     router3
10.0.0.4     router4

在/usr/local/rancid/var/devices/router.db中将两个id作为一个rancid数据库，输出如下：

router1:cisco:up
router2:cisco:up

我希望能够运行一个只能查找主机名routerx的脚本，并找到哪些尚未添加到router.bd routerx:cisco:up的主机名。

所以我在上面的例子中寻找的输出是：

打印缺少路由器

router3
router4

端

你能帮忙解决一些问题或指出我正确的方向吗？

Answer 1

你可以使用这个awk：

awk -F '[: ]+' 'FNR==NR {a[$1]; next} !($NF in a) {print $NF}' router.db hosts
router3
router4

<强>解释

-F '[: ]+'  # Use custom field separator as 1 or more of colon or space
FNR==NR     # for first file populate an array `a` with key as $1
next        # keep reading 1st file till EOF is reached
!($NF in a) # from 2nd file execute {...} if last fieild in NOT in array a
{print $NF} # print last field from hosts file

Answer 2

尝试：

routerdb="/usr/local/rancid/var/devices/router.db"

while read _ router; do
  grep -q "^$router:" $routerdb || echo "Missing: $router"
done < /etc/hosts

Answer 3

您可以通过以下方式完成： -

awk -F'\t' {'print $2'} /etc/hosts > temp.txt
awk -F':'  {'print $2'} /usr/local/rancid/var/devices/router.db > temp1.txt
cat temp.txt | while read a
do
     i=`grep -c $a temp1.txt`
     if [ $i -eq 0 ]
     then
          echo $a
     fi
done

这将打印路由器3＆amp;路由器4 ..

Answer 4

在比较文件时，

diff通常是一个不错的选择。完整的解决方案可能如下所示：

#!/bin/bash

ROUTERDB=/usr/local/rancid/var/devices/router.db 
HOSTS=/etc/hosts

# use a temporary directory:
DIR=$(mktemp -d)
cd ${DIR}

# write first field of router.db in one file, using : as delimiter:
awk -F: '{ print $1 }' ${ROUTERDB} > routerdb
# write second field of hosts in the other:
awk '{ print $2 }' ${HOSTS} > hosts

# compare the two files, select only lines not in 
# router.db, and remove the + sign at the beginning:
echo Missing routers
diff -u routerdb hosts | grep "^+[^+]" | tr -d "+"
echo end

# remove temporary directory:
rm -rf ${DIR}

仅列出与文件2中的文件1不匹配的缺失信息

4 个答案: