DNS Propagation [closed]

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I have pointed the A record for the domain www.fitnaturally.co.uk (domain has been in use for a while) to my server IP (79.170.44.156). I did this 8 hours ago and still nothings happened. From my experience this process doesn't normally take any longer than 4 hours.

After doing a DNS Propagation check at http://www.whatsmydns.net/#A/www.fitnaturally.co.uk/

I have discovered that the correct IP is in some locations but in others it is still the old A Record ip (91.208.99.12). When i keep checking whatsmydns the IP address for each location keep changing back to the old IP also. For example London, UK (BT Global) was 79.170.44.156 but it has now changed back to (91.208.99.12).

If i do a DNS Prop check for http://www.whatsmydns.net/#A/fitnaturally.co.uk/ all A records show 79.170.44.156. But the old website still loads and I cannot connect to the new server via ftp.fitnaturally.co.uk.

Can somebody suggest anything that I can try to get this working or suggest a reason why its taking so long?

Answer 1

Your DNS records have 1-day TTLs, so that's how long it can take for old data to clear out of caches.

$ dig www.fitnaturally.co.uk a @ns1.tsohost.co.uk +norec

; <<>> DiG 9.6-ESV-R4-P3 <<>> www.fitnaturally.co.uk a @ns1.tsohost.co.uk +norec
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 7116
;; flags: qr aa; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 0

;; QUESTION SECTION:
;www.fitnaturally.co.uk.        IN  A

;; ANSWER SECTION:
www.fitnaturally.co.uk. 86400   IN  A   79.170.44.156

86400 seconds is 1 day. I'm assuming you had the same TTL on the old record that this replaced.

If you want changes to propagate more quickly, you have to lower the TTL. Note that this has to be done BEFORE you make the change, since caches get the TTL when they look up the old data, and hold on to it for that long before checking again.

To answer the inevitable next question: no, there's no way to force caches to clear.

Answer 2

In some cases, DNS propagation may take even more than one day. Use Google DNS 8.8.8.8, which is usually fast, to see if the change was correctly applied.