Transfer Domain (properly called this process a re: not to be confused with the process transfer a domain from one registrar to another) begins with an application to change the list of NS-servers. Typically, the application is submitted to the Registrar’s website (in Control Panel) by specifying the new NS-addresses of servers that need to produce redelegation domain.
When making changes to the registry depends on the settings of the registrar and is usually less than 30 minutes.
But then begins a procedure that usually causes the most confusion and even negative, and can take up to several days: on the DNS-servers, Internet service providers, through which access to the portability domain, not the actual cached more information about the values of the old records of his zone.
To understand why this depends on the inertia of the DNS servers of Internet providers, make a small technical digression and consider the domain information stored on NS-servers to which it has delegated.
The domain information stored on NS-servers, and has a unified structure comprising standard parameters regardless of the type of domain. We are interested in a parameter called TTL (Time to live, time to live). This parameter specifies the time the relevance of data caching queries (in seconds). It is in this setting guided DNS-servers of Internet providers, when they decide – to give in response to a request old information or go to NS-domain server and request a new one.
The value of the lifetime depends entirely on the will of the administrator NS-server domain. Selecting it, the administrator is guided by different considerations, and the most common of these considerations – how to minimize the number of calls to its NS-servers. It is clear that the larger the TTL value will expose the administrator, the less DNS-servers, Internet service providers will look to its NS-servers by caching the previously obtained data about the domain and giving them to end users.
During this time domain transfer plays a strictly negative role: all clients ISP, DNS-server is cached information about the portable domain, will receive outdated information over time, not less than that indicated in the TTL domain zone carried on the old NS -server. For example, if the TTL is equal to 86400, updating data on the portable domain will be delayed at least a day.