Shell script for packet capture when the NIC is very large in linux

I shamelessly turned the Amin Linux script around, and sometimes it might be used when checking.

#!/bin/sh

#
# Setup Area
#

Snif_if=eth0
pkg_threshold=7000
Save_dir=/home/snif_log
snif_count=2000

#
# don ' t change
#
[!-D $SAVE _dir] && mkdir-p $SAVE _dir
While:;
Todo

Pkg_cur= ' sar-n DEV 1 2|grep $SNIF _if|head-n 2|tail-n 1|awk ' {print $} ' |cut-d.-f1 '
#如果sysstat以12小时 (AM,PM) time, then take it again to get the correct result
["X$pkg_cur" = "x$snif_if"] && pkg_cur= ' sar-n DEV 1 2|grep $SNIF _if|head-n 2|tail-n 1|awk ' {print $} ' |cut- D.-f1 '

If [$PKG _cur-gt $PKG _threshold];then
Tcpdump-n-I $SNIF _if-c $SNIF _count-vs0-w $SAVE _dir/$SNIF _if. ' Date +%m%d-%h%m '. Cap
#tcpdump-N-i $SNIF _if-c $SNIF _count-w $SAVE _dir/$SNIF _if. ' Date +%m%d-%h%m '. Cap
Fi

Sleep 300
Done