Crontab job not writing output to a file

Question

I wanted to create a simple script that monitors a TCP connection status (through nc).

I tested it with success on a RedHat server:

* * * * * nc -z -v -w5 <host> <port> | while IFS= read -r line; do echo "$(date +"\%F \%T") $line"; done >>/tmp/status.txt

The output is OK to the file status.txt

Then I decided to export this line to my Raspberry (Raspbian)

I'm using the root user :

[root]$ crontab -e
* * * * * nc -z -v -w5 xx.xx.xx.xx yy | while IFS= read -r line; do echo "$(date +"\%F \%T"') $line"; done >>/root/status.txt

The file is created in /root/ but nothing is wrote into the file

I tried to place the file elsewhere (/home/pi), chmodded it, .... nothing worked.

I activated the cron log into rsyslog and the log doesn't show any error.

Any idea?