Linux Small Knowledge Translation-dynamic dns"(DDNS)

This conversation "dynamic dns".

DNS has been introduced last week, is to provide the host name and IP address the structure of the corresponding relationship. "Dynamic dns" is a structure that provides a dynamic management of the corresponding relationship between host name and IP address.

The previous DNS did not take into account the changing IP address situation. However, IP addresses are often changed in networks that use DHCP to assign IP addresses. Therefore, the same host name points to a different host each time.

Using the "Dynamic dns" "mentioned earlier, even if the IP address changes, the hostname and the changed IP address will automatically correspond.

Dynamic DNS is often used in personal servers. In most broadband lines, individual-facing individuals are IP addresses that are dynamically assigned from vendors. Therefore, each time the connection is disconnected, another IP address is reassigned.

In this case, using dynamic DNS, the hostname will automatically correspond to the changed IP address, so the server application of the non-fixed IP is possible.

As above, with Dynamic DNS, you can simply use a server with a host name. But there is a problem in it. In Dynamic DNS, but when the IP address changes, this change is reflected in the DNS that takes some time.

During this time, the hostname and IP address do not correspond correctly, and the host name may point to other hosts. Therefore, using a server with Dynamic DNS can be a little risky.

There are a number of negative views from security regarding the use of servers through dynamic DNS.

For-profit purposes the server uses dynamic DNS to make sure that there is a certain risk that even personal use of the server, when using dynamic DNS, also consider its dangers.