This is an interesting one - I’ll look into why there wasn’t a timeout here, but for the root cause, are you able to check your system logs on that target to see why the SFTP connection didn’t go through? Depending on your distro, you can usually find this info in /var/log/secure or /var/log/messages - I wonder if you have fail2ban or some other ratelimiting software that saw the multiple connection attempts in short succession and enacted a block.
We did not see any error messages, just the successful connection until it stops for 2 days and then the successful connections after we restarted everything, No errors or failed attempts.
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