how to flush the dns on Fedora 25

How to flush the dns on Fedora 25. I cannot see my website on Fedora 25 which used to work OK on Firefox on my desktop. Everyone else can see it including my laptop again with Fedora 25 connected to the Network cable.
It is suggested that I flush the dns but cannot find how to do it on Fedora.
Any help would be appreciated.how to flush the dns on Fedora 25

In general Linux doesn't cache lookups like Windows.

There ARE tools that may do it depending on what you're doing.

If the Linux system itself is a DNS server it might be a "caching DNS" server and you'd have to explore that.

I once found someone (the infamous "they") had turned on nscd which is Name Service Caching Daemon on a couple of servers. No one ever admitted doing so. Turning it off stopped the caching it was doing. If you're relying on it bouncing it might clear the cache.

Some tools do their own caching (e.g. Veritas NetBackup) and have their own methods for clearing cache.

You might also want to verify the entry you're seeing isn't in your local hosts file.

Check /etc/nsswitch.conf to see how you have lookups going (e.g. dns? files? nis+? etc...)

It might be just the browser cache that needs flushing. (I sometimes have to do that if I've changed networks while using firefox for example.)

Originally Posted by ferrari It might be just the browser cache that needs flushing. (I sometimes have to do that if I've changed networks while using firefox for example.)

I have done that nothings changed. I can connect using Firefox as a user not root and it works fine. have flushed the dns cache as well no joy.

Are you using a proxy perhaps? That might explain why user account works, but not as root.

Originally Posted by ferrari Are you using a proxy perhaps? That might explain why user account works, but not as root.

Thanks tried both no proxy and proxy no Joy. I guess this is not solvable I think I have tried everything, it just stopped working yesterday for no apparent reason. I have even run clamscan and rk hunter no joy. Every other website works OK.

I have just found out my site works Ok if I do not use Https:// it only works with http. Any ideas anyone.

http uses port 80 by default and https uses port 443 by default (i.e. if you're not specifying the port in the URL).

It may be your web server is allowing http but not https in the Apache setup or it may be you've not opened port 443 in the firewall.

Originally Posted by MensaWater http uses port 80 by default and https uses port 443 by default (i.e. if you're not specifying the port in the URL). It may be your web server is allowing http but not https in the Apache setup or it may be you've not opened port 443 in the firewall.

Thanks, No have found my provider has found the same problem and they are attempting to fix it.

Based on this new development then it shouldn't make a difference as to whether you were running firefox as root or not.

Originally Posted by ferrari Based on this new development then it shouldn't make a difference as to whether you were running firefox as root or not.

That's true. It was my providers back end that was the problem, but I had to reset the cache in any event.

Really weird problem though.

Happy Christmas and Joyous New year to everyone that helped.