We're calling on all EU-based Mozillians with iOS or iPadOS devices to help us monitor Apple’s new browser choice screens. Join the effort to hold Big Tech to account!

This site will have limited functionality while we undergo maintenance to improve your experience. If an article doesn't solve your issue and you want to ask a question, we have our support community waiting to help you at @FirefoxSupport on Twitter and/r/firefox on Reddit.

Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

Èròjà atẹ̀lélànà yii ni a ti fi pamọ́ fọ́jọ́ pípẹ́. Jọ̀wọ́ béèrè ìbéèrè titun bí o bá nílò ìrànwọ́.

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

  • 1 èsì
  • 4 ní àwọn ìṣòro yìí
  • 1 view
  • Èsì tí ó kẹ́hìn lọ́wọ́ user1929

more options

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!

Ọ̀nà àbáyọ tí a yàn

Does it work if you also set these preferences?

  • network.dnsCacheEntries to 0.
  • network.dnsCacheExpiration to 0.
  • network.dnsCacheExpirationGracePeriod to 0.
Ka ìdáhùn ni ìṣètò kíkà 👍 0

All Replies (1)

more options

Ọ̀nà àbáyọ Tí a Yàn

Does it work if you also set these preferences?

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