On 9/8/26 7:13 AM, dan wrote:
Hello,
I just started to wonder if in front of a sudden update of an hosting firewall
(such as vultr, digital ocean, hetzner, etc) or a refreshed public ip address
there is any danger that any active ssh connection can get closed down.
Is generally speaking too complex for these basic firewalls close down active
connections on the fly or I need to worry seriously about my remote backups ?
from experience, it is trivial for a cheesy firewall
to break active connections of any kind.
My personal experience has been that many times, commercial
firewalls will break long, persistent connections (to recover
states, I presume) if there is no traffic for a period of time,
even if the formal closing of the TCP connection hasn't taken
place. I've seen this with shell sessions in many cases, and
usually setting up some kind of keep-alive on the SSH client
solves the problem nicely.
I've not seen this happen with backups, where a data flow is
taking place (for cheap, home-grade routers, all bets are off,
of course).
BUT as someone who has backed up many terabytes of data with
rsync over ssh over a few decades, monitoring the results of
your backup and figuring out how to deal with problems observed
must be part of your backup plan...but in my experience,
dropping ssh connections is just one of many reasons you need
to monitor them. You always need to worry about your backups.
Nick.
