Firewall Issues - ssh_dispatch_run_fatal errors during SSH

Hi

Disabling the firewall can not be a solution.

Since macos 15.0.1 is using OpenSSH it could be a cipher problem.

Following parameter cipher add works now for an hour!

ssh -c aes256-gcm@openssh.com user@targethost

works also with

ssh -c chacha20-poly1305@openssh.com user@targethost

Hi

Disabling the firewall can not be a solution.

Since macos 15.0.1 is using OpenSSH it could be a cipher problem.

Following parameter cipher add works now for an hour!

ssh -c aes256-gcm@openssh.com user@targethost

works also with

ssh -c chacha20-poly1305@openssh.com user@targethost

But it helps only for 1, 2 hours then the behaviour comes back.

tbirdvet wrote:

Did not last long with firewall off. For me the solution was to turn off WiFI and only use ethernet.

Please understand that this issue happens with everything, wireless or ethernet, as it doesn't depend on the network interface. I have a docking station with ethernet and I get it every now and then. You're just lucky you didn't get it in this short period of time. Give it long enough time and it will happen again.

The most painful part of this issue is that people keep tinkering with things, and then one thing fixes the issue temporarily, and everyone yells "eureka"... like I said before, the internet is literally flooded with "MacOS network timeout issues", and everyone thinks they got a fix, but eventually it comes back, and people don't have time to track this and most of the time they prefer to just restart MacOS. The core issue is still there though. I do really hope Apple will fix it (and part of me is happy that Sequoia made the issue quite pronounced, so that it gets fixed once and for all). I did report the issue through feedback assistant, and have proven that it's an issue in MacOS. Let's wait and see.

My issue may be somewhat different from this original issue posted here. I had a web page that would only open about 1/2 of the time (happened several times a day). After trying all settings I found another link from another user indicating it may be related to having both ethernet and WiFi on at the same time (service order has ethernet first). But after turning off WiFI no more web page loading issues for the last two days so I'm keeping my fingers crossed. Never had this issue prior to Sequoia 15.0.1

Same problem here .... 2 weeks ago I upgraded from 14.7 to 15.01 ... ever since my ssh connections are *very* flaky; the breakdown anywhere between 15 minutes and 2 hours, with the same error message:

Bad packet length 1345936880.
ssh_dispatch_run_fatal: Connection to 210.7.46.210 port 22: Connection corrupted

Trying the *trick* others mentioned in places (adding a specific cipher) gave me this immediately:

ssh_dispatch_run_fatal: Connection to w.x.y.z port 22: message authentication code incorrect

I also experience issues w/ e.g. vSphere/vCenter ... virtual consoles disconnect spontaneously at random times (independent of the browser session from which the were spawned, the session remains active, just the console disconnects).

Downgrade back to 15.0 until Apple gets it together. How to download and install macOS - Apple Support

Disabling private rotating mac in the network settings solved the issue for me

Upgraded to 15.0.1. Bug still present. Turning off "Limit IP address tracking" seems to work. How ever did you figure that out?

(Nope—connection dropped after 20 minutes)

Nope—connection dropped the same way after 20 minutes.

Updated to 15.0.1 and disconnects have not disappeared but they went WAY down.

Disconnects can be 20 mins to 2 hours instead of every 2-20 mins!

I can live with this but it's still not ideal.

The issue still existed in 15.0, just less severe but it is there. Disabling the firewall will work for now as I don't feel like downgrading since it is working after that change.

Mine was set to Fixed. I am trying Off to see if it fixes.

Did not last long with firewall off. For me the solution was to turn off WiFI and only use ethernet.