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In Firefox Quantum running on Windows Server 2016, is there any way to clear/flush the DNS cache in the browser?

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  • Last reply by user1929

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When switching onto VPN, we have an address that will resolve from an external IP address to an internal IP address (and back when getting off of VPN). The problem is, Firefox appears to hold on to the old DNS to IP resolution for a long period of time. This makes our website inaccessible until the old IP address drops and the browser initiates a new DNS request. Changing the network.dnsCacheExpiration value in about:config to something lower does not solve/improve the issue.

There was a browser add-on named DNS Flusher which used to be available to help with this problem, but now the developer says that in Quantum the API that the add-on relied on is no longer available. PLEASE HELP!

When switching onto VPN, we have an address that will resolve from an external IP address to an internal IP address (and back when getting off of VPN). The problem is, Firefox appears to hold on to the old DNS to IP resolution for a long period of time. This makes our website inaccessible until the old IP address drops and the browser initiates a new DNS request. Changing the network.dnsCacheExpiration value in about:config to something lower does not solve/improve the issue. There was a browser add-on named DNS Flusher which used to be available to help with this problem, but now the developer says that in Quantum the API that the add-on relied on is no longer available. PLEASE HELP!

Chosen solution

Does it work if you also set these preferences?

  • network.dnsCacheEntries to 0.
  • network.dnsCacheExpiration to 0.
  • network.dnsCacheExpirationGracePeriod to 0.
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Seçilmiş Həll

Does it work if you also set these preferences?

  • network.dnsCacheEntries to 0.
  • network.dnsCacheExpiration to 0.
  • network.dnsCacheExpirationGracePeriod to 0.