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Comment by Geezus_42 | Hacker News Reader

I've never used a computer that didn't have occasional hiccups. The Mac I have for work has lots of weird bugs. One is that if it has been using WI-FI and I plug-in my dock with an Ethernet cable attached, I lose internet access because MacOS can't gracefully handle the new interface becoming available.

I also find Apple's choice to just continually create 1G swap files until the system locks absolutely baffling.

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> One is that if it has been using WI-FI and I plug-in my dock with an Ethernet cable attached, I lose internet access because MacOS can't gracefully handle the new interface becoming available.

macOS has a 'service (priority) order':

* https://sixcolors.com/post/2025/05/service-please-manage-mul...

It's no different that having multiple default gateways in Linux (with different metric/priorities):

* https://superuser.com/questions/1600190/change-order-of-rout...

And when your default route changes so will the TCP connection end-points. This is mostly an issue when you have a stateful session, like SSH, and less so with 'bursty' traffic like web surfing or e-mail.

By default wired connections are higher priority. I've been on Wifi with a MacBook and patched in with the Network Settings panel open and see the change, which is reflected in the output of "netstat -rn". Underneath the hood most of the macOS kernel is (Free)BSD/Unix.

Until we get SCTP multihoming popularized this will generally be an issue on any operating system. Though it would perhaps be nice to perhaps have a socket (TCP) API flag to tell the kernel "keep me on the initial interface as long as it exists" so sessions don't flip over.

I've never experienced this behavior with a Linux or Windows machine.

I'm not talking about sessions dropping. It has the symptoms of an IP conflict, absolutely no traffic can pass until I disable Wi-Fi. Any other laptop I have ever used would just switch, maybe drop an SSH session, but not this.

There's also the fact that I can never trust the clipboard to actually copy when I tell it to. Several of my co-workers have expressed the same issue, so it's not just me. Sometimes, no matter whether I use the context menu or ctrl+c, it just doesn't copy what I have highlighted and paste whatever the last thing I copied was instead.

Can any OS gracefully handle switching between WiFi and Ethernet without at least a blip in connectivity?

Without a blip maybe not but is it noticeable?

I've been regularly plugging/unplugging my usb-c docking connected to ethernet while being on teams video call without issues on both linux and windows but ultimately it depends on the protocol. Web/https stuff is usually more forgiving thanks to sessions being maintained "externally" from the protocol itself. Copying files via sftp be a different experience I reckon because you usually use a different source ip address when you switch and need to initiate a new connection.

if it's just about connectivity then yes, that should be normal, a OS should only switch the default interface _iff_ the interface it switches to is up and ready.

Idk. about desktop Linux, but my phone does the (WLAN -> Mobile) switch just fine.

If it's about _not reconnecting_ (e.g. which for many apps might require some manual pause/resume of streamed data or similar), then things are more complex as you can't keep your IP, so it then depends on weather the application uses HTTP3/Quick or similar protocols in implementations which are designed to be able to freely roll over to different IP addresses.

So both yes and no :)

In my experience Linux can yeah.

It works fine with my Linux Laptop.

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