AsusMerlin(koolshare)Router-network-checker

checknetwork.sh

#!/bin/sh
# name: koolshare联网检测+自动重启网络脚本
# scriptFilePath: /koolshare/scripts/checknetwork.sh
# referenceLink: https://post.m.smzdm.com/p/a25dgzmq/
# 
# usage:
# vim /jffs/scripts/services-start
# #!/bin/sh
# #services-start创建定时任务添加本脚本，每2分钟一次检测网络，多次探测均断网则自动重新拨号
# /usr/sbin/cru a checknetwork "*/2 * * * * /bin/sh /koolshare/scripts/checknetwork.sh"
# 
#联网探测url(主站点)
try_url=www.baidu.com
#联网探测url(备用站点)
backup_url=www.example.com
#超时时间(秒)
try_timeout=5
#检测重试次数
retry_times=3

#curl检测
function check_curl()
{
    #获取响应状态码
    local ret_code=`curl -I -s --connect-timeout ${2} ${1} -w %{http_code} | tail -n1`
    if [ "x$ret_code" = "x200" ]; then
        #网络畅通
        return 1
    else
        #网络不畅通
        return 0
    fi
    return 0
}
#ping检测
function check_ping()
{
    #筛选错误关键词
    local err_num=`ping -c 1 -W ${2} ${1} 2>&1 |grep -E "100% packet loss|bad address"|wc -l`
    if [ "$err_num" -eq 0 ]; then
        #网络畅通
        return 1
    else
        #网络不畅通
        return 0
    fi
    return 0
}
#重启网络
function restart_wan()
{
    /usr/bin/logger -c "无法连接互联网，准备重新拨号！"
    killall pppd
    /usr/bin/logger -c "已断开拨号连接,延时10秒..."
    sleep 10
    /usr/bin/logger -c "正在重新拨号..."
    /usr/sbin/pppd file /tmp/ppp/options.wan0 >/dev/null 2>&1 &
}

#检测主逻辑
i=1
try_times=`expr ${retry_times} + 1`
while [ "$i" -lt "$try_times" ]; do
    check_curl $try_url $try_timeout
    curl_res=$?
    check_ping $try_url $try_timeout
    ping_res=$?
    /usr/bin/logger -c "第${i}次网络检测,url:${try_url},curl:${curl_res},ping:${ping_res}"
    if [ "$curl_res" -eq 1 ]&&[ "$ping_res" -eq 1 ]; then
        break
    fi
    #对调切换主备探测url
    tmp_url=$backup_url
    backup_url=$try_url
    try_url=$tmp_url
    #延迟重新检测
    sleep 15
    i=$((i + 1))
done
# 重试了多次，最后仍然有至少一种方式无网络，重新拨号
if [ "$curl_res" -eq 0 ]||[ "$ping_res" -eq 0 ]; then
    restart_wan
    check_curl $try_url $try_timeout
    curl_res=$?
    check_ping $try_url $try_timeout
    ping_res=$?
    /usr/bin/logger -c "重新拨号后网络检测完成,url:${try_url},curl:${curl_res},ping:${ping_res}"
    exit -1
else
    /usr/bin/logger -c "网络检测完成,本次网络正常"
fi
exit 0