Set the Interface Down if Monthly Traffic Limit Exceeded

outbound-limit.sh

#!/bin/bash
# date: 2024-05-21
# license: GPLv3 https://www.gnu.org/licenses/gpl-3.0.txt
# author: nanpuyue <[email protected]> https://blog.nanpuyue.com

# 设置接口名称和流量限制
IFACE="eth0"
LIMIT="190 GiB"

# vnstat 数据库文件路径
VNSTAT_DB="/var/lib/vnstat/vnstat.db"

while read line; do
  [ "$line" = MODIFY ] || continue
  # 使用 vnstat 检查接口流量
  if ! vnstat -i $IFACE --alert 0 3 m tx $LIMIT; then
    echo "Monthly transmitted data limit exceeded. Set $IFACE down."
    # 将接口设为 down
    ip link set $IFACE down
    break
  fi
# 使用 inotifywait 监控 vnstat 数据库文件的修改
done < <(inotifywait -qme modify --format %e $VNSTAT_DB)