I faced the issue and hope this will be helpful for someone
I had key based authentication for sync user with strict password policy, and after the password expiry day,
I got following error
WARNING: Your password has expired.
Password change required but no TTY available.
rsync: connection unexpectedly closed (0 bytes received so far) [sender]
rsync error: error in rsync protocol data stream (code 12) at io.c(463) [sender=2.6.8]
chage -m 0 -M 99999 -I -1 -E -1 user
# check user password expiry date
chage -l ashishnepal
# force password next time
chage -m 0 ashishnepal
# Never expire
chage -m 99999 ashishnepal