Mac DNS resolution failure

[MartyF]

I'm a recent subscriber to Sky broadband and had no problems connecting my iMac, MacBook Pro and phones via WiFi. A week ago I shut down my iMac while on holiday, and on rebooting it I find I have a connection to the router but no internet. All my other devices are working fine. A network diagnostic test on my iMac returns a DNS Resolution Failure message. I've tried disconnecting and reconnecting to the router and rebooting the iMac but no luck. On checking the DNS Servers details they appear to be the same as on my MacBook, which is working fine. Can anyone help please?

[Chrisee]

@MartyF Apples error messages can be confusing but assuming you do have a DNS issue the DNS settings on the Sky hub are hardwired so if you use the automatic setting you will be using Sky's default servers. These can occasionally have issues but when they do we get loads of posts. I would reboot your Macbook as it could simply be a start up error.  

However if the issue persists you can try what I do myself which is to manually add a public DNS to the list in the Network settings for the Sky connection so 192.168.0.1 (the hub) 8.8.8.8 and 8.8.4.4 (Google's public DNS)

[MartyF]

Thanks for that @Chrisee. Before I got a chance to try out your suggestion, my internet connection suddendly sprung into life for some unknown reason.

[Carine]

WiFi is working fine on other devices but on my Mac I'm getting internet for one minute, my connection then stops, this happens after restarting - waking up the MAC. This is a new issue. MAC Diagnostic says it's a DNS issue. Have added 8.8.8.8 and 8.8.4.4 but that doesn't change my issue. 

[MartyF]

Hi @Carine 

My problem was with the internet connection rather than WiFi but it was cured by restarting the router. Don't know if that would help but worth a try.