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DHCP broken for Mac OS catalina

Upgrade to Catalina with no hickup. but now DHCP for networking refuse to work. WIFI or ethernet. WHen manually configure the IP address then it would not go to the internet.


Anybody knows what happen here?

Posted on Oct 16, 2019 8:03 PM

Reply
20 replies

Oct 18, 2019 8:24 AM in response to sakura240

try to confirm if SOCKS proxy turned on. You can check that by going system preferences>network> wi-fi (or ethernet)> advanced> proxies > and untick SOCKS proxy.


I also would advise you to try:

https://support.apple.com/en-gb/HT202663

https://support.apple.com/en-gb/HT201974


and last but not least to try to do safe mode and to reset smc, here's the articles for that:

https://support.apple.com/en-gb/HT201262

https://support.apple.com/en-gb/HT201295


In last resort create a test user and see if it works on the test acc:

https://support.apple.com/en-gb/HT204443

Oct 18, 2019 5:29 PM in response to MittensPS

Thanks for the response. A piece of it worked. Sort of...


I turned off firewall and confirmed firewall was "off" on both existing profiles. Still no access.

SOCKS Proxy was not active on either profile.

I found this article and did this before posting problem: https://support.apple.com/en-gb/HT202663

I found this article and did this before posting problem: https://support.apple.com/en-gb/HT201974

As for safe mode... I also did that before posting problem. Since the article said Wireless Networking would be limited or unavailable, I didn't expect much. https://support.apple.com/en-gb/HT201262

I did not reset SMC.


I then created a Test user profile (firewall off, no password). It worked and then it didn't, then it did, and then it didn't. I accessed the test account, opened Safari and clicked on the Weather Channel link. The page opened. I closed the browser and then logged out of the profile. When I logged back in to take screen shots of the WiFi settings, the browser hung for a few minutes--the progress bar showed about 1/8 th progress and stopped. After waiting about 3 minutes, I clicked on the Weather Channel link again and this time I got the "Safari Can't Connect to the Server" message. I realized that I was still logged into my primary profile so I logged out of the primary and then back into the test without shutting down. No change. Safari still hung. SO... I shut down and started back up in the test account. It worked! I even surfed a bit!

I took screen shots of wifi configs and also checked login items (there were none). I stepped away and the monitor went into sleep mode. When I woke it, I could no longer connect. I powered down, powered up, accessed the test profile and launched safari and all was working gain. Note that this was not a restart. I did not test that.

Thoughts?


Oct 20, 2019 6:11 PM in response to Jayronn

I tried a few things and remembered a few things since my last post. I deleted my other profile so now all I have are my primary and my test profiles. I downloaded and ran etrecheck and noticed my BootCamp drive. I restarted in Windows and had no short term internet connectivity issues. I say short term because I just checked a few sites and logged out. Today I noticed that if I continued to browse in the test profile, the internet would drop after a bit of surfing. Once it dropped in about 20 or 30 minutes, another time it took an hour. I did the etrecheck before and after the drop. Here are the full Working and Nonworking logs:



Oct 24, 2019 7:56 AM in response to Jayronn

How to back up your Mac - Official Apple Support


I’ve also used Carbon Copy Cloner to generate storage clones, and have used those for backups.


I’ve previously used Disk Utility for backups, but have had a few (arcane) issues with that in recent efforts. I was able to restore those.


I have photos stored locally on the Mac and not in iCloud. Your usage and settings may differ.


Oct 16, 2019 9:26 PM in response to sakura240

I have the same issue on my mid 2015 MBP 15 Retina (MacBookPro11,5). I installed Catalina on 10/13. Since then, I can connect to wifi (I tried 2 different networks), get Apple Software Updates, News notifications, Weather updates and Messages but no DHCP. Installed browsers (Safari, Chrome, Firefox) cannot access any network. I tried to submit feedback through the Feedback Assistant but it hangs up on login--"There was a problem connecting to the server." Which reminds me, I am also unable to connect to my Apple ID in System Preferences.

In troubleshooting, I have tried:

  • Deleting and Re-adding WiFi settings in Network. (Yes, I applied changes after deleting.)
    • Unable to add a new DNS server.
  • Installing all (one) 'Software Updates' that have been made available.
  • Uninstalling (deleting) Virus software
  • Uninstalling (deleting) VPN software
  • Moving LaunchDaemons and LaunchAgents to a temporary location and restarting
  • Zapping the PRAM
  • And probably one or two more items I don't remember.

I don't have an rj45 adapter to try Ethernet vs Wifi but according to this post, that won't work either.

For the time being, I own a $2k paperweight. I looked to Apple for support but they wanted to charge me for their mistake. That's not something I'm prepared to do.

Help?

Oct 18, 2019 8:21 AM in response to Jayronn

I have worked with Apple support and we narrow it to disable Apple Firewall to get the network to work correctly with DHCP Luckily I have a 3rd party FW (Bitdefender Netbarrier) that I can use so I don't have to rely on Apple Firewall (which is really limited). We are going to try to connect again this Sunday to try to get to the bottom about why Apple FW decide to block something at the network level. (I used to have both Apple FW and Netbarrier running in High Sierra, and I did not change any of the previous rule within the network setting after the update).


Maybe you can try to disable the firewall and see if that's help. Will post more after my troubleshoot session this coming Sunday.

Oct 18, 2019 8:30 AM in response to sakura240

Try to create a test user account with administrator rights, try to see as well if you have login items, its strange that apple firewall is causing that.

Can you try to go into Recovery and test your wi-fi there?

just hold cmd+r while Mac is starting and try to connect to wi-fi then click on "get help online" and see if it shows and results

Oct 18, 2019 9:54 AM in response to sakura240

What I usually have found in terms of networking issues is that

some network preference gets borked. What I have done is under

System Preferences->Network, create a new "Location", select the

interface on the left, then click "Advanced..." and on the TCPIP

pane set the DHCP and then click renew lease.


If you are using WiFi, delete the connection and connect again.

Oct 18, 2019 10:07 AM in response to MrHoffman

Agree with you that Apple FW issue is a big miss. That's why we are going to get back and continue to troubleshoot on Sunday. I have a work aorund at this time with using Netbarrier instead. Apple FW is only and application layer FW anyway, a bit lacking in granularity but I'd like to understand why it was broken after the update. It is definitely not Netbarrier issue as we able to eliminate that as a culprit in the troubleshooting process.

Oct 18, 2019 10:31 AM in response to sakura240

sakura240 wrote:

Agree with you that Apple FW issue is a big miss.


You’re misinterpreting my skepticism.

DHCP testing is inherent in accessing most any network, and would be tested in a vast number of networks.

Which leads to investigating what might be unique about this network, this DHCP server, and related details.


That's why we are going to get back and continue to troubleshoot on Sunday. I have a work aorund at this time with using Netbarrier instead. Apple FW is only and application layer FW anyway, a bit lacking in granularity but I'd like to understand why it was broken after the update. It is definitely not Netbarrier issue as we able to eliminate that as a culprit in the troubleshooting process.


So to confirm, you’ve tried this DHCP request on your network without any add-on firewalls, without any added security apps, and without any added anti-malware apps?


if you’ve tested that, Apple has several different macOS firewalls around just to add to the confusion.


You’ll want to try this Mac on a different network, too.

Oct 19, 2019 12:31 AM in response to Jayronn

Please download and run EtreCheck, then open a new reply here and then press the button that looks like a printed page to open up a text input box big enough to paste the entire EtreCheck hardware and software configuration report into the new reply here. From the EtreCheck report, we’ll get details on your hardware and software configuration, and maybe also some indication of what’s (not) going on here.


Socks proxies are only typical in corporate and organizational environments, or when otherwise looking to re-route and to centralize HTTP/HTTPS network access... unusually.

Oct 23, 2019 7:27 PM in response to MrHoffman

A few things... I went to the Nord VPN site and their answer to removal was "Look at the Apple Support page that covers uninstalling software." Basically, go to the Applications folder and delete the application (Which is what I did.)

As for Flash, I had to watch a video for school. I downloaded flash, watched the video and deleted Flash.

I'm at the point where I'm about to make sure all my photos and files are backed up and then do a clean install. That would really upset me.

Oct 24, 2019 8:17 AM in response to sakura240

I had this same problem pop up out of the blue the other day . I tried everything with no cure.


I ended up doing a time machine restore back a couple of days and the problem went away .


No help but not sure what broke . Before that I got a message that the Mac mini restarted itself because of a problem , with no hint to what that problem was .




DHCP broken for Mac OS catalina

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