Internet issues on Monterey

by the way, most of the udp (open)sockets are created by macos mdnsresponder not AnyConnect. If you use 'netstat -anxv | grep -e udp' you can see the corresponding PID for each UDP socket, then you can have a look at your process list to check what that PID is for.

example for PID 309:

udp4 0 0 *.58521 *.* 786896 9216 309 394 0x0103 0x00010000

_mdnsresponder 309 0.0 0.0 33892620 10516 ?? Ss 8:26am 0:13.32 /usr/sbin/mDNSResponder

Adding to my own and others' earlier posts...

My employer also pushes a regular patch to Cisco AnyConnect about every day or two and this adds in the second instance of "Cisco AnyConnect Socket Filter" in the Network Preferences column on the right side of the panel. Effectively, this breaks DNS and connectivity. A simple removal of this restores connectivity and I go back to the same time interval of a day or two of unfettered connectivity, then cycle repeats. I have observed this for the last week.

Better situation, but still not completely fixed. It appears Cisco has opened a case with Apple and we can only hope that this is addressed in an update soon. FWIW, I updated to the latest version of AnyConnect from my work.

I'll repost if there are any material changes to the situation and appreciate others' comments very much!

-FightingIbis

Thanks! This is a great answer. I also have AnyConnect and have been losing my internet connection about once per day since the Monterey upgrade.

Two things about Apple:

(1) I called Apple Support they told me to uninstall AnyConnect because "Monetery doesn't like VPN". Obviously this is not possible for me because I need to WFH, but the support person sounded too bored to care.

(2) In this thread the "Apple recommended" answer is completely irrelevant.

It's crazy that we are stuck between Apple and Cisco :-(

I just downloaded and upgraded to the latest version of AnyConnect and now the race condition is gone (anyconnect-macos-4.10.04071-predeploy-k9). I did have the same issue with AnyConnect/DNS before now

I had the same problem. This is what worked for me:

In the System Preferences --> Security and Privacy --> Firewall I had blocked emlog.pl from receiving incoming connections. After allowing incoming connections, everything started working again.

The problem occurred again, despite of my previous answer. And I 'solved' it again... This time what worked for me:

The were two routers set as router in my household: the modem from my ISP is from ZTE, model H369A, and TP-Link Archer AX10.

Ok, now I've set the TP-link from Operation Mode to Access Point Mode.

Hope this helps!

It turns out you're right. The UDP sockets aren't limited to the ephemeral ports; they can use all unrestricted ports. But port exhaustion does not seem to be the issue anyway. It's some other resource that's being exhausted, although I still haven't figured out which one. The low-level error that comes back when exhaustion has occurred is EADDRNOTAVAIL, which can be the result of several problems.

However, having a number of 93966 (and increasing) is a reliable indication that the problem is occurring on your system and that eventually, some resources will be exhausted, requiring a reboot. I have a healthy BSD server running, and that number always remains below 100.

I'm still experiencing this issue once per week on macOS 12.1 and Cisco AnyConnect 4.10.04071.

I had connection issues since day 1. Doesn’t matter if I’m using home Wi-Fi or make iPhone hotspot. No matter what browser either. Sometimes just nothing helps so I use my PC.

Sometimes everything works just fine. It’s really weird. Have to shut down vpn for sure too.

While my previous 2 answers are not wrong, I still encountered the same problem. And again I did 'solve' it:

I am using somewhat outdated (latest firmware update: 2018) power line adapters (TP-link TL-WPA8630P V2) to connect from one room to the next.

When I encounter the problem I also notice the power line icon on my power line adapter is off. If I remove both power line adapters from the power socket and put them back in after a few moments all connectivity is restored.

Only while using Ethernet did I have a problem connecting this morning, when turning on WiFi everything worked as expected.

Thank you. I'll give that a try. I have a 16-inch upgraded to Monterey and have to use Cisco Anyconnect for work. It will function 6-8 hours then loses internet DNS, cycling WIFI on/off does nothing, and reboot is required. I kicks off side-kick Ipad as well.

This is an issue with Intel-based Macbook Pros running Monterey 12.1 and AnyConnect Client 4.9+  It appears AnyConnect Client 4.8.00175 is extremely stable on Monterey 12.1. I installed it yesterday and confirmed stats on UDP protocol remains below 100 at all times using command 

netstat -anxv -p udp | wc -l

With newer versions of AnyConnect client 4.9+, stats exceed 150,000.  Please uninstall your current version of AnyConnect client on your Macbook Pro with Monterey 12.1 and install 4.8.00175

My WiFi has problems connecting after opening. Often I have to turn off Wifi and turn it back on a couple of times. Then, when it is connected, the icon in the menu bar still shows connecting or not connected. Takes a few minutes to connect.

Also, when I open an app, it doesn't open focused. I have to press Command+Shift+Tab to focus it.

This OS wasn't tested very well.

MacBook Air M1, macOS 12.0.1

Monterey is horrible! I can't open links in emails, I get weird Safari error messages, and often can't open pages in Safari. Making Chrome my default browser hasn't helped. Is there an easy way to revert to the previous OS?

macOS 12.2 is out now, you may go ahead and upgrade. It seems Apple has resolved the bug on this release. I've done some tests, and it seems the behavior with Cisco AnyConnect also has changed and UDP sockets are no longer the problem.