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donatj

Eternal Terminal ‘et’ is like Mosh but functionally better. Doesn’t break scrollback. Transparent to tmux control mode.

I switched from Mosh to et across 12ish servers around 6 months ago and am way happier for it.

https://eternalterminal.dev/

Previous conversation:

https://news.ycombinator.com/item?id=21640200

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ET uses a layer above TCP to make connections persistent, while mosh uses UDP which is better for high-latency or flaky connections (like 4G or wifi). For the use case in the original post with a congested wifi network, mosh is probably going to provide a better experience.

I use Blink on my iPad, as it supports mosh for ssh connections. As iPadOS sets limits for background execution and quickly kills apps, it is great to be able to reconnect to your running session.

Looking at Eternal Terminal, it doesn't have the same "local echo" feature that minimises the effect of latency in a cli environment.

Thats the trade-off. The "local echo" feature is what I use mosh for as I deal with system 8 to 10 timezones away. Doing this breaks scrollback.

I guess when mosh was first made, this was a problem with ssh shell sessions over EDGE or 3G as well, although network latency is less of a concern these days on 4G LTE or 5G mobile.

What about using GNU screen inside a mosh connection like that:

    mosh server -- screen -xRR -D

You then can use the scrollback buffer provided by screen with Ctrl-a, ESC and then the usual Up/Down and PgUp/PgDown buttons.

Yeah, I do something similar with tmux. You can even get mouse scrollback to work properly by setting the option in the conf file.

Here some medium article about this -

https://medium.com/@toja/tip-using-mosh-with-scrollback-257a...

For some reason scrollback mouse integration works well till one disconnects and reconnects, and then suddenly it's broken.

The lack of scrollback is what stopped me from using mosh before. I never knew about Eternal Terminal, but I've just installed it and it seems to work well (my issue is unreliable connections, rather than latency, so the lack of prediction doesn't affect me as much)

ET has the somewhat undesirable characteristic that if you cat /dev/random or some other large file, you're going to have to kill the ET process if you want your terminal back. Mosh does not suffer from that

Having extremely little knowledge of how these things work and thus a strong personal resistance to them (I only started using tmux recently, and exclusively with iTerm’s integration for its “control center” mode, just so I don’t lose sessions if my SSH disconnects), I’m seeing a lot of setup and caveats and am a bit scared off by these. This one looks nice because it has scrollback (essential) but it seems to require a bunch of installation on the remote? I have SSH on all my machines already; is there not something that can bootstrap a session from just that?

There are moments that tmux's persist session won't work well such as opening nested SSH sessions to another machine with nested tmux to keep the session. Also, tmux does not handle SSH sessions, so if a SSH session disconnected (e.g. WiFi signal lost, your macBook gets sleep mode), you need to manually restart the SSH session and run tmux again, whereas Blink and ET never disconnects the SSH session.

On top of that, I use both tmux and Mosh at the same time. You don't need to use tmux exclusively.

I meant, you don't need to get scared. Both ET and Mosh built on top of SSH and there never be critical errors when dealing with their shell. Though both of them requires installations on the remote but they are a single zero-config packages: just install a package (not "a bunch of") and that's it. No config needed, even no background systemd services needed.

Right, I see how it can be more convenient but I also see caveats so I’m not sure if I should bother. I’m not really a fan of installing much, either: often I don’t really want to do a whole install to get into a machine (some random AWS for instance) or I just can’t (not my machine, no admin privileges, paltry package manager, …)

You can always try it on one machine and see if it makes your life better or not.

> There are moments that tmux's persist session won't work well such as opening nested SSH sessions to another machine with nested tmux to keep the session.

what difficulties are you facing there? i use tmux deeply nested without problems. one trick i use is to change the tmux command key to be something different on each nesting level.

> one trick i use is to change the tmux command key to be something different on each nesting level.

This is exactly the difficulty I never want to see...

If you just want a persistent connection, you never have to press the command key or even acknowledge it exists, do you? And you didn't answer what difficulties you've personally faced.

If I just want a persistent connection, then the nested tmux that takes 2+ useless lines in the bottom already falls into the "it doesn't work well" category.

And I what I said that the problem was the moment I have to have different tmux config for every machine, just like she/he is doing.

I guess I just don't understand why you need the tmux command key at all. If you pretended it didn't exist, what feature would you be losing out on that mosh has?

And when you're setting up a server it's easy to turn off the tmux status bar.

indeed. the only thing i need to do is copy a config file to set up the command key. the main use of the command key is to switch terminals and to access scrollback. beyond that, the key is rarely needed. working in any terminal is the same no matter how deep the nesting. i don't notice it.

the multiple toolbars don't bother me either. they can serve as a visual aid to recognize where i am. each terminal looks different. but in reality i don't pay much attention to them.

I've tried both. I've found (data point of one) that mosh is better in high latency network situations.

This doesn't resolve the latency and reactivity problems that the author mentions though.

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