1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
|
+++
date = 2022-03-23
title = "Dynamic DNS with Cloudflare API"
description = ""
draft = false
+++
# DDNS: Dynamic DNS
If you\'re hosting a service from a location with dynamic DNS (where
your IP may change at any time), you must have a solution to update the
DNS so that you can access your service even when the IP of the server
changes.
The process below uses the [Cloudflare API](https://api.cloudflare.com/)
to update DNS `A` and `AAAA` records with the
server\'s current IP. If you use another DNS provider, you will have to
find a way to update your DNS (or find a way to get a static IP).
First, install `jq` since we will use it in the next script:
```sh
sudo apt install jq
```
Next, create a location for your DDNS update scripts and open the first
script:
```sh
mkdir ~/ddns
nano ~/ddns/update.sh
```
The following `update.sh` script will take all of your
domains and subdomains and check Cloudflare to see if the current
`A` and `AAAA` records match your server\'s IP
address. If not, it will update the records.
```sh
# file: update.sh
#!/bin/bash
# Update TLDs
domains=(example.com example.net)
for domain in "${domains[@]}"
do
echo -e "\nUpdating $domain..."
zone_name=$domain /home/<your-username>/ddns/ddns.sh
done
# Update subdomains for example.com
domain=example.com
subdomains=(photos.example.com)
for subdomain in "${subdomains[@]}"
do
echo -e "\nUpdating $subdomain..."
zone_name=$domain dns_record=$subdomain /home/<your-username>/ddns/ddns.sh
done
```
Next, open up the `ddns.sh` script. Paste the following into
the script and update the `api_token` and `email`
variables.
```sh
nano ~/ddns/ddns.sh
```
**Note**: If you want your DNS records to be proxied through Cloudflare,
find and update the following snippet: `"proxied":false}"` to
say `true` instead of `false`.
```sh
# file: ddns.sh
#!/bin/bash
# based on https://gist.github.com/Tras2/cba88201b17d765ec065ccbedfb16d9a
# initial data; they need to be filled by the user
## API token
api_token=<YOUR_API_TOKEN>
## email address associated with the Cloudflare account
email=<YOUR_EMAIL>
# get the basic data
ipv4=$(curl -s -X GET -4 https://ifconfig.co)
ipv6=$(curl -s -X GET -6 https://ifconfig.co)
user_id=$(curl -s -X GET "https://api.cloudflare.com/client/v4/user/tokens/verify" \
-H "Authorization: Bearer $api_token" \
-H "Content-Type:application/json" \
| jq -r '{"result"}[] | .id'
)
echo "Your IPv4 is: $ipv4"
echo "Your IPv6 is: $ipv6"
# check if the user API is valid and the email is correct
if [ $user_id ]
then
zone_id=$(curl -s -X GET "https://api.cloudflare.com/client/v4/zones?name=$zone_name&status=active" \
-H "Content-Type: application/json" \
-H "X-Auth-Email: $email" \
-H "Authorization: Bearer $api_token" \
| jq -r '{"result"}[] | .[0] | .id'
)
# check if the zone ID is
if [ $zone_id ]
then
# check if there is any IP version 4
if [ $ipv4 ]
then
dns_record_a_id=$(curl -s -X GET "https://api.cloudflare.com/client/v4/zones/$zone_id/dns_records?type=A&name=$dns_record" \
-H "Content-Type: application/json" \
-H "X-Auth-Email: $email" \
-H "Authorization: Bearer $api_token"
)
# if the IPv6 exist
dns_record_a_ip=$(echo $dns_record_a_id | jq -r '{"result"}[] | .[0] | .content')
echo "The set IPv4 on Cloudflare (A Record) is: $dns_record_a_ip"
if [ $dns_record_a_ip != $ipv4 ]
then
# change the A record
curl -s -X PUT "https://api.cloudflare.com/client/v4/zones/$zone_id/dns_records/$(echo $dns_record_a_id | jq -r '{"result"}[] | .[0] | .id')" \
-H "Content-Type: application/json" \
-H "X-Auth-Email: $email" \
-H "Authorization: Bearer $api_token" \
--data "{"type":"A","name":"$dns_record","content":"$ipv4","ttl":1,"proxied":false}" \
| jq -r '.errors'
else
echo "The current IPv4 and DNS record IPv4 are the same."
fi
else
echo "Could not get your IPv4. Check if you have it; e.g. on https://ifconfig.co"
fi
# check if there is any IP version 6
if [ $ipv6 ]
then
dns_record_aaaa_id=$(curl -s -X GET "https://api.cloudflare.com/client/v4/zones/$zone_id/dns_records?type=AAAA&name=$dns_record" \
-H "Content-Type: application/json" \
-H "X-Auth-Email: $email" \
-H "Authorization: Bearer $api_token"
)
# if the IPv6 exist
dns_record_aaaa_ip=$(echo $dns_record_aaaa_id | jq -r '{"result"}[] | .[0] | .content')
echo "The set IPv6 on Cloudflare (AAAA Record) is: $dns_record_aaaa_ip"
if [ $dns_record_aaaa_ip != $ipv6 ]
then
# change the AAAA record
curl -s -X PUT "https://api.cloudflare.com/client/v4/zones/$zone_id/dns_records/$(echo $dns_record_aaaa_id | jq -r '{"result"}[] | .[0] | .id')" \
-H "Content-Type: application/json" \
-H "X-Auth-Email: $email" \
-H "Authorization: Bearer $api_token" \
--data "{"type":"AAAA","name":"$dns_record","content":"$ipv6","ttl":1,"proxied":false}" \
| jq -r '.errors'
else
echo "The current IPv6 and DNS record IPv6 are the same."
fi
else
echo "Could not get your IPv6. Check if you have it; e.g. on https://ifconfig.co"
fi
else
echo "There is a problem with getting the Zone ID. Check if the Zone Name is correct."
fi
else
echo "There is a problem with either the email or the password"
fi
```
Once the script is saved and closed, make the scripts executable:
```sh
chmod +x ~/ddns/ddns.sh
chmod +x ~/ddns/update.sh
```
You can test the script by running it manually:
```sh
./update.sh
```
To make sure the scripts run automatically, add it to the
`cron` file so that it will run on a schedule. To do this,
open the cron file:
```sh
crontab -e
```
In the cron file, paste the following at the bottom of the editor:
```sh
*/5 ** ** ** ** bash /home/<your_username>/ddns/update.sh
```
|
