封面图：

脚本代码：

#!/usr/bin/env bash
set -o errexit
set -o nounset
set -o pipefail


Automatically update your CloudFlare DNS record to the IP, Dynamic DNS

Can retrieve cloudflare Domain id and list zone’s, because, lazy

Place at:

curl https://raw.githubusercontent.com/yulewang/cloudflare-api-v4-ddns/master/cf-v4-ddns.sh > /usr/local/bin/cf-ddns.sh && chmod +x /usr/local/bin/cf-ddns.sh

run crontab -e and add next line:

*/1 * * * * /usr/local/bin/cf-ddns.sh >/dev/null 2>&1

or you need log:

*/1 * * * * /usr/local/bin/cf-ddns.sh >> /var/log/cf-ddns.log 2>&1

Usage:

cf-ddns.sh -k cloudflare-api-key

-u user@example.com

-h host.example.com  # fqdn of the record you want to update

-z example.com  # will show you all zones if forgot, but you need this

-t A|AAAA # specify ipv4/ipv6, default: ipv4

Optional flags:

-f false|true  # force dns update, disregard local stored ip

default config

API key, see https://www.cloudflare.com/a/account/my-account,

incorrect api-key results in E_UNAUTH error

CFKEY=填写你的cf-key

Username, eg: user@example.com

CFUSER=你的cf登录邮箱

Zone name, eg: example.com

CFZONE_NAME=你的主域名

Hostname to update, eg: homeserver.example.com

CFRECORD_NAME=完整子域名,例如 ddns.123.com

Record type, A(IPv4)|AAAA(IPv6), default IPv4

CFRECORD_TYPE=A

Cloudflare TTL for record, between 120 and 86400 seconds

CFTTL=120

Ignore local file, update ip anyway

FORCE=false

WANIPSITE=”https://4.ipw.cn”

Site to retrieve WAN ip, other examples are: bot.whatismyipaddress.com, https://api.ipify.org/ …

if [ “\(CFRECORD_TYPE" = "A" ]; then
:
elif [ "\)CFRECORD_TYPE” = “AAAA” ]; then
WANIPSITE=”https://4.ipw.cn”
else
echo “$CFRECORD_TYPE specified is invalid, CFRECORD_TYPE can only be A(for IPv4)|AAAA(for IPv6)”
exit 2
fi

get parameter

while getopts k:u:h:z:t:f: opts; do
case \({opts} in
k) CFKEY=\){OPTARG} ;;
u) CFUSER=\({OPTARG} ;;
h) CFRECORD_NAME=\){OPTARG} ;;
z) CFZONE_NAME=\({OPTARG} ;;
t) CFRECORD_TYPE=\){OPTARG} ;;
f) FORCE=${OPTARG} ;;
esac
done

If required settings are missing just exit

if [ “\(CFKEY" = "" ]; then
echo "Missing api-key, get at: https://www.cloudflare.com/a/account/my-account"
echo "and save in \){0} or using the -k flag”
exit 2
fi
if [ “\(CFUSER" = "" ]; then
echo "Missing username, probably your email-address"
echo "and save in \){0} or using the -u flag”
exit 2
fi
if [ “\(CFRECORD_NAME" = "" ]; then
echo "Missing hostname, what host do you want to update?"
echo "save in \){0} or using the -h flag”
exit 2
fi

If the hostname is not a FQDN

if [ “\(CFRECORD_NAME" != "\)CFZONE_NAME” ] && ! [ -z “\({CFRECORD_NAME##*\)CFZONE_NAME}” ]; then
CFRECORD_NAME=”\(CFRECORD_NAME.\)CFZONE_NAME”
echo “ => Hostname is not a FQDN, assuming $CFRECORD_NAME”
fi

Get current and old WAN ip

WAN_IP=curl -s ${WANIPSITE}
WAN_IP_FILE=\(HOME/.cf-wan_ip_\)CFRECORD_NAME.txt
if [ -f \(WAN_IP_FILE ]; then
OLD_WAN_IP=`cat \)WAN_IP_FILE`
else
echo “No file, need IP”
OLD_WAN_IP=“”
fi

If WAN IP is unchanged an not -f flag, exit here

if [ “\(WAN_IP" = "\)OLD_WAN_IP” ] && [ “$FORCE” = false ]; then
echo “WAN IP Unchanged, to update anyway use flag -f true”
exit 0
fi

Get zone_identifier & record_identifier

IDFILE=$HOME/.cf-id\(CFRECORD_NAME.txt
if [ -f \)ID_FILE ] && [ \((wc -l \)ID_FILE | cut -d “ ” -f 1) == 4 ]
&& [ “\((sed -n '3,1p' "\)ID_FILE”)” == “\(CFZONE_NAME" ] 
&& [ "\)(sed -n ‘4,1p’ “\(ID_FILE")" == "\)CFRECORD_NAME” ]; then
CFZONE_ID=\((sed -n '1,1p' "\)ID_FILE”)
CFRECORD_ID=\((sed -n '2,1p' "\)ID_FILE”)
else
echo “Updating zone_identifier & record_identifier”
CFZONE_ID=\((curl -s -X GET "https://api.cloudflare.com/client/v4/zones?name=\)CFZONE_NAME” -H “X-Auth-Email: \(CFUSER" -H "X-Auth-Key: \)CFKEY” -H “Content-Type: application/json” | grep -Po ‘(?<=“id”:“)[^”]’ | head -1 )
CFRECORD_ID=\((curl -s -X GET "https://api.cloudflare.com/client/v4/zones/\)CFZONE_ID/dns_records?name=\(CFRECORD_NAME" -H "X-Auth-Email: \)CFUSER” -H “X-Auth-Key: $CFKEY” -H “Content-Type: application/json” | grep -Po ‘(?<=“id”:“)[^”]’ | head -1 )
echo “\(CFZONE_ID" > \)ID_FILE
echo “\(CFRECORD_ID" >> \)ID_FILE
echo “\(CFZONE_NAME" >> \)ID_FILE
echo “\(CFRECORD_NAME" >> \)ID_FILE
fi

If WAN is changed, update cloudflare

echo “Updating DNS to $WAN_IP”

RESPONSE=\((curl -s -X PUT "https://api.cloudflare.com/client/v4/zones/\)CFZONE_ID/dns_records/\(CFRECORD_ID" 
-H "X-Auth-Email: \)CFUSER”
-H “X-Auth-Key: \(CFKEY" 
-H "Content-Type: application/json" 
--data "{"id":"\)CFZONE_ID”,“type”:”\(CFRECORD_TYPE","name":"\)CFRECORD_NAME”,“content”:”\(WAN_IP", "ttl":\)CFTTL}“)

if [ “\(RESPONSE" != "\){RESPONSE%success*}” ] && [ “\((echo \)RESPONSE | grep ““success”:true”)” != “” ]; then
echo “Updated succesfuly!”
echo \(WAN_IP > \)WAN_IP_FILE
exit
else
echo ‘Something went wrong :(’
echo “Response: $RESPONSE”
exit 1
fi

设置定时任务，每2分钟检查一次并执行：

任意目录下，使用root权限，执行： [pre]crontab -e[/pre] 选择第一个nano打开；

添加每次执行的代码：

*/2 * * * * /root/ddns/ddns.sh >> /root/ddns/ddns.log 2>&1

注意，按照你自己的文件所在的地址，别忘记修改文件路径

设置定时清除日志：

0 0 * * * > /root/ddns/ddns.log

每天定时0点清除所有的log信息。

特别注意：

不同于你手动bash执行文件，/root/ddns/ddns.log 和 /root/ddns/ddns.sh都需要给与权限，默认644权限，给它755权限。