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I administer a few sites and need to update their DNS entries from time to time, e.g., adding an A-record point certain subdomain to a certain IP.

When I check sites like http://www.opendns.com/support/cache/, I can clearly see the DNS change taking effect throughout the world - is it just my PC that can't see this change (ping newsubdomain.example.org says it cannot resolve host name)

The network "map" is like this:

My PC -> my router -> my ISP's router -> internet

On my PC, the DNS is set automatically which means that if I run iconfig /all, my router will be returned as the DNS server (192.168.1.1).

On my router, the DNS is set to be what my ISP provided me with.

Is this correct? What can I do to see new hostnames resolved quicker?

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up vote 2 down vote accepted

The DNS server on your router (or at your ISP) is probably caching responses for existing records which is usually good, since it takes away load on upstream servers. Depending on the software running on the router you might be able to disable caching or lower that time but this will of course only affect your own network. Keep in mind that other users might suffer from the same problem. The correct way would be to only lower the TTL value of your entries in the authoritative servers to some minutes and wait for the time given in the old TTL value. After that time you can change your records and they should be also effective on other caching servers within the time period given in the new TTL value. After that you can rise the time again to reduce load on the authoritative server and and slower queries for the users.

If the problem also occurs on new subdomains that did non exist before, you probably cannot do much since you probably have no influence on the TTL, as it is often not changeable by the normal user on usual DNS services.

To know which server is caching the response for how long, you can run nslookup -debug yourdomain dnsserver on your router's, your ISP's and on your authoritative DNS servers.

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