2. DDNS (Dynamic Domain Name System)
• DDNS (Dynamic DNS) is a service
that maps Internet domain names to
IP addresses.
• Unlike DNS that only works with
static IP addresses, DDNS is designed
to also support dynamic IP
addresses, such as those assigned by
a DHCP server.
[2]
3. • That makes DDNS a good fit for
home networks, which often receive
dynamic public IP addresses from
their Internet provider that
occasionally change.
• Dynamic DNS (DDNS) is the ability
for a host to update its own DNS A
record.
[3]
DDNS (Dynamic Domain Name System)
4. • A host's IP address (or what appears
to be its IP address) can change
when you use a home broadband
service such as cable or DSL.
• If you have a broadband connection,
DDNS allows you to have a full-time
Internet server even though you
don't have a static IP address.
[4]
DDNS (Dynamic Domain Name System)
5. •To use DDNS, one simply signs up
with a DDNS provider and installs
network software on their host
to monitor its IP address.
–For example, dyndns.com provides
a free dynamic DDNS service via
software that can run on Windows,
Mac or Linux computers.
[5]
DDNS (Dynamic Domain Name System)
6. • In cases if a website is hosted on a
server with dynamic IP, each time
you connect to the internet, a
temporary IP address is assigned to
the server by the Internet Service
Provider. So when the IP address of
the server changes you will not be
able to access the website using
Domain name. [6]
DDNS (Dynamic Domain Name System)
7. • In such cases the Dynamic DNS will
take care of this issue by changing
the IP address of your website
correspondingly.
[7]
DDNS (Dynamic Domain Name System)
9. • All DDNS service providers require
that you use a DDNS client on your
web server that will periodically
update the IP address information in
your provider's DDNS record.
• One of the most commonly used
clients is DDclient.
[9]
Install a DDNS Client On Your Server
10. • Like most RedHat and Fedora Linux
software products, DDclient is
available in the RPM format.
• You can usually download the
software from your DDNS provider,
or you can find it at rpmfind.net.
[10]
Install a DDNS Client On Your Server
11. • The RPM name usually starts with
ddclient followed by a version
number, as in ddclient-3.6.3-
1.noarch.rpm
• Its configuration file is
/etc/ddclient.conf file
[11]
Install a DDNS Client On Your Server
12. • Username: Your DDNS account's
login name
• Password: Your DDNS account's
password
• Use: The method used to determine
the IP address to advertise to the
DDNS server
[12]
The most important general parameters
to configure are:
13. • Server: The name of the DDNS
provider's main DNS server
• Protocol: The methodology the
DDNS client should use to
communicate with the DDNS server
• Your domain: The domain to which
your web server will belong
[13]
Some important DDNS provider
parameters are
14. 1) You can configure DDclient to start
at boot time using the chkconfig
command:
[root@bigboy tmp]# chkconfig ddclient on
[14]
How to Get DDclient Started
15. 2) You can start, stop, and restart
DDclient after boot time using the
DDclient initialization script as in:
[root@bigboy tmp]# service ddclient start
[root@bigboy tmp]# service ddclient stop
[root@bigboy tmp]# service ddclient restart
[15]
How to Get DDclient Started
16. 3) Testing Your Dynamic DNS
[root@bigboy tmp]# host www.my-
site.com
Server: 127.0.0.1
Address: 127.0.0.1#53
** server can't find www.my-site.com:
NXDOMAIN
[16]
How to Get DDclient Started
17. 3) Testing Your Dynamic DNS
[root@bigboy tmp]# host www.my-
site.com
Server: 127.0.0.1
Address: 127.0.0.1#53
** server can't find www.my-site.com:
NXDOMAIN
[root@bigboy tmp]# host www.my-site.com
ns1.minidns.net
www.my-site.com has address 97.158.253.26 [17]
How to Get DDclient Started