One thing that irked me a bit with Firefox was the dns caching. Particularly with my work OWA, I have the habit of checking my email first and then if needed, firing up my VPN client and logging in. Once I did that, I either have to wait for a long time for the browser DNS to pick up the new network and/or restart the browser all together.
I found this blogger’s note about Firefox DNS settings.
- In the Firefox address bar window, type
about:config - Filter for
dns - You will get several options that can be modifed by double-clicking on the value. I was able to set the
network.dnsCacheExpirationfrom the default 3600 to 10. I am assuming this is measured in seconds - Viola! Logging in and out of VPN will not adversely affect my DNS settings.

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