rsync -ar --password-file=/etc/rsyncd.demo.pas /tmp/ demo@10.29.80.11::accesslog if 10.29.80.11 is not alive ( or dead ) , it will go on !
I believe you mean by "go on" that it will hang? (Rather than go on to the next command?) If so, you should check to see what rsync is doing. For instance, run it under strace (or the equivalent for your system). The most likely thing is that it is hanging at the connect() call. If you want rsync to timeout, pass the --contimeout=N (connect timeout) option to have it timeout after N seconds. If the above isn't an accurate understanding of your issue, feel free to respond with more details.
No response. Use of --continmeout should hopefully fix things for the user.