You can make a difference in the Apple Support Community!

When you sign up with your Apple Account, you can provide valuable feedback to other community members by upvoting helpful replies and User Tips.

Looks like no one’s replied in a while. To start the conversation again, simply ask a new question.

DNS Resolution Failure

My Mac Pro is failing to connect to the internet.

It happens when I first log in. It usually lasts for 5 minutes.

I only use WiFi to a Google Mesh Router, which is new (Google Fiber).

I can text and use email, but my browsers won't budge (Safari, Firefox and Chrome).


I ran Network Diagnostics and it reported "DNS Resolution Failure" (below).


But, after about 5 minutes, the computer seems to figure it out and runs normally.


I checked with my iMac and it has the same DNS settings and never has a hang or network problem?


So, I'm convinced there is something else going on with my Mac Pro.

All my other devices, an iMac and Mac Book all work normally - never have this problem.


When I looked up the information attached to the error report, is says to go to the WiFI Preference and Advanced option. Then go to the DNS tab and add OpenDNS or GoogleDNS. I can't enter any text in those fields - only hex values are allowed?


The DNS IP address is correct - it's the same one my iMac uses.


I'm not sure what to do next. What ever it is, it eventually fixes itself.







Posted on Nov 13, 2021 9:24 AM

Reply
Question marked as Top-ranking reply

Posted on Nov 13, 2021 10:41 AM

Yes, that is my Google Router IP.


After I changed the DNS to 8.8.8.8, it seemed to be working smoothly.

Then I put it to sleep.

When I got back on, the network was hung again.

I ran Network Diagnostics again and it now has 3 notices.

I don't think it liked the 8.8.8.8, but I haven't changed it back.




Similar questions

12 replies
Question marked as Top-ranking reply

Nov 13, 2021 10:41 AM in response to lllaass

Yes, that is my Google Router IP.


After I changed the DNS to 8.8.8.8, it seemed to be working smoothly.

Then I put it to sleep.

When I got back on, the network was hung again.

I ran Network Diagnostics again and it now has 3 notices.

I don't think it liked the 8.8.8.8, but I haven't changed it back.




Dec 17, 2021 4:53 PM in response to Mac_Cat

I just found another clue.

My computer name is getting changed daily.

I renamed the computer in Sharing, thinking it might conflict with another computer name.

But, when I check on it, I find it's been bumped up, like a file name than has been copied and repeated.



The other odd thing I just found was that I had a Thunderbolt cable with both ends plugged into the back of the computer!? Obviously, that was a stupid mistake, but it didn't appear to be noticed - diagnostics didn't catch it and all my Thunderbolt devices (disc arrays, monitors, camera, etc.) worked normally.


I had several system crashes last week, but nothing this week.


I'm losing faith in the H/W, so I'm planning to replace the compute with a newer one.

Nov 13, 2021 10:09 AM in response to Mac_Cat

What is 192.168.86.1? Is it the IP address of your router?

Your router setting can then point to a real DNS server. The default one would be the ones used by your internet provider.

If there is a blip in the internet provider DNS server it may not work correctly for a short time.


Here is what the Mac's help says about search domain

Domain Name System (DNS) servers map domain names to Internet Protocol (IP) addresses. When used in conjunction with search domains, they allow you to go quickly to websites and servers you visit frequently without typing the complete address.

For example, if you specify the search domain apple.com, typing “store” in your web browser takes you to store.apple.com. Or, if you use campus.university.edu as a search domain, you can type “server1” in the Connect To Server dialog in the Finder to connect to server1.campus.university.edu.

Nov 13, 2021 10:45 AM in response to Mac_Cat

Ian is not a valid top-level domain when last I checked (lots and lots of top-level domains are being added, so “squatting” in unregistered domains and unassigned top-level domains has gotten a whole lot more hazardous), and Ian is a somewhat unusual choice for a default domain, yes.


If you were to enter “Faust” as your DNS query and not the full host name, adding your default “Ian” domain will get you “Faust.Ian” (technically “Faust.Ian.”) Which is a bargain that best not exist.


That value for your default domain and your DNS forwarder are both arriving from the local router via DHCP.


192.168.68.1 is presumably your router IP address, and that box presumably running a DNS forwarder.


You can restart the router and see if that clears this, or check the router settings for DNS servers. And default domain.


Common “public” open DNS servers are 1.1.1.1 (Cloudflare), 8.8.4.4 (Google), 8.8.8.8 (Google), and 9.9.9.9 (Quad9). Other such services are available.

Nov 13, 2021 10:51 AM in response to Mac_Cat

The settings here arise from the DHCP server, which is usually in the router. Unless you set your client to use a static IP address and configuration, the client will use DHCP from the router. Your router is mis-set or malfunctioning, or whatever DNS is selected at the router is mis-set or malfunctioning, or there’s a connectivity issue or block between the firewall and the firewall-specified DNS server. Given the use of “Ian” here, this router config is already somewhat suspect.

Nov 13, 2021 11:21 AM in response to Mac_Cat

Mac_Cat wrote:

Since my other 2 Macs are set the same way and working, I was convinced the Router was OK. But, I will re-boot the router tonight.

FYI. I was not able to edit or the “lan” from the Search window?!


The DNS addresses and the default domain are configured on the network router; on the box running the DHCP server.


While you’re logged into the network router, also check its firmware version and update that too if there’s newer available.


Nov 15, 2021 8:47 AM in response to MrHoffman

My router is a Google Nest Mesh router.

There is no way I know of to log into it with a browser.

Instead, they insist I use the "Google Home" app on my iPhone.

That has no way to force a firmware update, but it appears to be current (13729.57.27).


I realize the router is set for dynamic DNS and DHCP - there is no option to over ride or even edit the settings.


I downloaded EtreCheckPro and ran it. It has a few clues - one of which was excessive CPU us and high internal temps. So, then I installed a Fan app and increased the fan speed. (I cleaned it out a few months ago - lots of dust bunnys).


And, I'm also thinking is a problem on my Mac Pro, since my MacBook and iMac have no such problem and the same settings.

One of the differences is that the Mac Pro has TechTool Pro (version 14) on it. I'm growing more suspicious of it. It reports that everything is OK.


I also haven't run it in safe mode, but I'm just not sure what help that would give me. I have all kinds of applications loaded that have never given me any problems until my upgrade to Monterey. I have nothing in my start-up, but I don't know how to kill the TechTool daemons or uninstall the application. That's the direction I'm thinking might help.


I already removed all the outdated games (Steam, COD, etc.).




I have not had a chance to restart the router, however, and that's also on my list.

Dec 23, 2021 1:40 PM in response to Mac_Cat

SOLVED: Thunderbolt cable problem


I had mistakenly inserted both ends of the same thunderbolt cable to the computer.


I'm surprised this didn't cause H/W error messages anywhere.

Wireless Diagnostics didn't catch it.

ErteCheck Pro and TechTools didn't catch it, either.


When I removed the thunderbolt cable, the network delays ceased immediately and have not returned.


The other cause was my system name kept being changed (see above).


So, I'm guessing that Thunderbolt uses some kind of network resources that got confused looking for the system and finding it, thinking it was a different computer with the same name. I never thought much of that error, because it had happened a few times with an old MacBook that I don't use very often. Sometimes, that MacBook would report another computer using the same name, so I assumed that was really a duplicated IP and blamed (DNCP) from my failing Airport router ( I have since replaced it ).




DNS Resolution Failure

Welcome to Apple Support Community
A forum where Apple customers help each other with their products. Get started with your Apple Account.