You have detached Mosh sessions on this server


There’s a ton of tech I take for granted but barely discuss. Mosh has received all but one blog mention here, but I use it daily. I consider it mandatory for administering FreeBSD, NetBSD, and Linux servers in remote availability zones.

Mosh sessions are specifically designed for fault tolerance. Unlike SSH, if you drop a connection, Mosh will continue to keep the session alive for you to reattach. No more ah crap, did I run that session inside a screen?!

The side effect of this is you may encounter these when you re-connect to a server:

Mosh: You have 2 detached Mosh sessions on this 
server, with PIDs:
    - mosh [49443]
    - mosh [80599]

If you don’t need them, just kill their process. Too easy:

# kill 49443

This also unintentionally demonstrates FreeBSD PID randomisation; specifically increment randomisation. Linux doesn’t support them, for better or worse depending on who you speak to. I concede they’re no panacea, and random PIDs can introduce their own problems, but security is abouy layers. It’s good FreeBSD affords us the option.

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