MacOS issue (Sequoia 15.4.1 and earlier)

I think it is likely something that is installed is creating an incompatibility that could be causing this.

For instance, I do exactly what you are doing (put Mac to sleep, move to a new wireless environment) almost every day as do scores of my colleagues, most of whom never shut down or restart their Mac laptops, but I hjave never heard of this being reported. We are all on 15.4.1. I use both an Intel MacBook Pro and an M3 MacBook Pro, neither displays those symptoms.

So I would look carefully at what is installed. For instance, you have Bitdefender installed. Anti-virus extensions and software are never needed on Macs and when installed, frequently create issues, especially when MacOS upgrades or updates are applied.

Simply disabling or turning off such security software is not enough; it really needs to be completely uninstalled and removed with a comprehensive tool; usually the vendor provides that.

Given that the /System folder and the OS itself are now a cryptographically signed and sealed immutable volume, it's not possible for the OS to become "corrupted" after updating. That would render the cryptographic seal invalid, which would be a fatal issue rendering the computer un-bootable on Apple Silicon.

Whatever your issue is, it is in the parts of the system you are allowed to modify, such as System Extensions or Network Extensions such as modern content filters. Bit Defender is a logical culprit (you mention having run it for years - but has it recently been updated?), but so could any other networking add-ons you may be using, such as firewalls, VPN, endpoint security extensions...its a pretty extensive list in theory.

In case the issue occurs again, can you please try closing the Apple Mail app only? - This has solved similar issues with me in 15.4.1. When network traffic was disturbed for me, Activity Monitor indicated such traffic, however it does not appear to show that Mail is generating this traffic.

But when the Mail app is closed, the traffic disappears.

Generally, Mail generates this traffic at my mac for a limited amount of time. So the problem was that it happened and then disappeared periodically. Strange behavior however, and only happened after the last 2 updates.

So, there was a Filter/Proxy enabled that I wasn't aware of that was proxying DNS queries, and when I disabled that, when I come back from sleep, networking works instantly as I would expect.

Good reminder to truly verify what SW is running, even when you think you know.

Netskope support just confirmed to us that it's because of this. Starting 15.4. Fix in the upcoming Netskope v126...

Many of the users here do not sleep their newer Macs as they have SSDs and not HDDs. There have been a lot of issues with sleep on Macs and most of the response recommended not using the sleep mode but have the screensaver kick in and then go dark after a set amount of time. I don't have a laptop but many of those that do recommend shutting down when moving to a new location or over night.

The only way to definitely make sure it's not any 3rd party software is to restore the Mac to factory setting and move while sleeping and then try Safari. If it's the problem persists it's an issue with sleep mode and not any 3rd party software. If not then you need to do some digging and testing.

We use GlobalProtect VPN at work -- it's required to access our network resources. Been working great for for the last couple of years we've been using it. Until the latest MacOS Update. Now I can not access SMB shares on our Azure cloud in the VPN. I also cannot call our REDIS with redis-cli even though, again, this all worked flawlessly beforehand. And in addition some of our APIs now report invalid hostname. I can get some of this fixed by constantly re-flushing the DNS cache and killing the listener with terminal, but I shouldn't have to.

I really feel Apple broke something networking-wise with the latest update and it's quite frustrating.

What's worse is that if I go into Windows 11 ARM 64 using Parallels, I *CAN* reach all those resources, so clearly GlobalProtect isn't blocking them and there's no real networking issue there with Parallels routing Windows traffic through it. This is strictly about the MacOS networking libs used by native MacOS apps that's giving me serious troubles.

Could it be how the Check for New Mail settings is set to?

Try setting it to Manually and see if that makes any difference.

If you think the phenomenon is definitively linked to Safari (and/or other browsers as per the similar issue you mention), then you need to be looking at what Safari settings or add-on extensions may be causing this - including ones bundled with third-party programs like your AV.

Do keep in mind however, that a similar outcome multiple years (and OS versions) apart could have radically different causes.

I have seen this same issue with my Mac with the latest versions of Sequoia. I have the notebook set to go to sleep mode when I close the lid. I don't want to leave it plugged in all the time, and the battery will drain if it doesn't go into sleep mode.

I see this problem with Chrome, not Safari, but DNS stops working, and websites freeze on restore from sleep. After 4 or 5 minutes, the problem goes away, and things work normally. It doesn't happen every time coming back from sleep, but the majority of times it does. I can't reboot things every time there's a problem, it would take 10 minutes to reboot and get everything fully loaded again.

Any other troubleshooting you can think of besides DNS checks, pings to websites?

lansoar wrote:

thanks for the input. I disagree on the need for AV. Mac's are not immune, and they are increasingly targeted.

First, there is no reason to ever install or run any 3rd party "cleaning", "optimizing", "speed-up", anti-virus, VPN or security apps on your Mac.  This documents describe what you need to know and do in order to protect your Mac: Effective defenses against malware and other threats - Apple Community and Recognize and avoid phishing messages, phony support calls, and other scams - Apple Support.  

There are no known viruses, i.e. self propagating, for Macs.  There are, however, adware and malware which require the user to install although unwittingly most of the time thru sneaky links, etc.   

Anti Virus developers try to group all types as viruses into their ad campaigns of fear.  They do a poor job of the detecting and isolating the adware and malware.  Since there are no viruses these apps use up a lot of system resources searching for what is non-existent and adversely affect system and app performance.

There is one app, Malwarebytes, which was developed by a long time contributor to these forums and a highly respected member of the computer security community, that is designed solely to seek out adware and known malware and remove it.  The free version is more than adequate for most users.  

Unless you're using a true VPN tunnel, such as between you and your employer's, school's or bank's servers, they provide false security from a privacy standpoint.  Read these two articles: Public VPN's are anything but private and Security Risks: The Dangers of Using Free VPNs (eccu.edu).  

That being said you won't find one experienced user here that agrees with youi on AV apps.