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I migrated DNS Nameservers from old to new 1 month ago but still on some local internet providers it shows old DNS information. According to whatsmydns.net it's propagated properly but some service providers locally haven't cleared their cache. Is there any way to give it a hard push so the DNS cache of these local internet service providers will be cleared automatically.

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closed as off-topic by Tero Kilkanen, Greg Askew, Ward, MadHatter, Andrew B Jan 9 '17 at 8:34

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    No, there is no hard push or cache clear in DNS. Without further information on the issue like the domain name and configuration, there isn't anything we can help with. – Tero Kilkanen Jan 8 '17 at 11:34
  • Thanks for the reply but how can you help if I will give you domain name? I already said it's propagated everywhere except few internet service providers. My main questions is how to ping them so they will clear their DNS cache. – Ahmad Hussain Jan 8 '17 at 12:04
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    Why not just contact the support department of those service providers? – Thomas Jan 8 '17 at 12:18
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    @AhmadHussain If we are to accept it at face value that everything is correctly/consistently set up (your problem suggests that it may not be), then there is indeed no need for your domain name or configuration. I suppose you should see it as a gracious attempt to address your actual problem rather than just answering your question. – Håkan Lindqvist Jan 8 '17 at 13:19
  • @HåkanLindqvist I have uploaded configuration but I can't upload domain information. I did all configurations on digitalocean and according to digitalocean everything is fine but why I was worried that some providers still haven't cleared their cache that's why it's not being accessed. Also in zone file TTL is 1800. I have uploaded screenshot of zone file too. – Ahmad Hussain Jan 9 '17 at 7:06
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No, there is no means within DNS itself to force someone else's caching servers to clear their cache.


The caching, as defined in the protocol, is purely time-based; the authoritative server specifies the maximum time that the returned record sets are allowed to be cached (the TTL) and caching servers are expected to adhere to this.

It's well known that there are cases where TTLs are not adhered to, especially in cases where the specified TTL is very low, but it's definitely not something that should be expected on the scale where it's a problem a month after making changes.

It appears much more likely that your problem is not actually about caching and that something is incorrectly set up either on your end or on this ISP's end.

On your end, ensure that:

  • The delegation is consistent with your authoritative records (NS records in your zone should agree with the NS records in the parent zone, same goes for any glue (A/AAAA)).
  • All your nameservers respond consistently, ie they all have identical zone data. If you are doing anything fancy like split horizon/views, ensure that this setup actually works as expected.

If that was not the problem you will probably want to reach out to the affected ISP and try to get them to look into whatever the problem is (presumably something on their end).

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