Why is bash rsync script not writing anything to file?

Question

Ubuntu 9.10

crontab -l

0 1 * * * /root/cron/rsync-93.193.99.111 &> /root/cron/rsync-93.193.99.111.log
0 3 * * * tail -100 /root/cron/rsync-93.193.99.111.log | msmtp me@myemail.com

ls -l /root/cron/rsync-93.193.99.111.log

-rw-r--r-- root root /root/cron/rsync-93.193.99.111.log

The rsync-93.193.99.111.log file displays zero size in Nautilus.
I get an email, but it's empty.
Running tail -100, also shows emtpty output, so the email is correct.

Why is the bash rsync script not writing anything to the file ?

Answer 1

I believe it's because &> is not supported in sh which is the shell that cron uses. Use the explicit form:

0 1 * * * /root/cron/rsync-93.193.99.111 > /root/cron/rsync-93.193.99.111.log 2>&1

Also, you can do sudo crontab -e instead of doing sudo su then crontab -e.

Answer 2

I concur with Dennis's assessment of your problem. But I have a couple of other points to mention.

Most importantly, don't do this:

0 1 * * * some command
0 3 * * * some other command that should run after the first one

What if the first command takes more or less than two hours? To make sure that the second command runs when the first finished, put them on a single line:

0 1 * * * /root/cron/rsync-93.193.99.111 >/root/cron/rsync-93.193.99.111.log 2>&1; tail -100 /root/cron/rsync-93.193.99.111.log | msmtp me@myemail.com

Also, you might want to take advantage of cron's automatic mailing of errors. (This assumes your system is set up properly for mail, which may not be the case if you have to run msmtp rather than mail.)

MAIL=me@myemail.com
0 1 * * * /root/cron/rsync-93.193.99.111 2>&1 | tee /root/cron/rsync-93.193.99.111.log | tail -n 100