diff --git a/entrypoint.sh b/entrypoint.sh
index 0813991..8c21d1e 100644
--- a/entrypoint.sh
+++ b/entrypoint.sh
@@ -2,7 +2,7 @@
 
 CRON_CONFIG_FILE="/etc/crontabs/root"
 
-echo "${CRON} python /opt/crane.py" > $CRON_CONFIG_FILE
-echo "@reboot python /opt/crane.py" >> $CRON_CONFIG_FILE
+grep -qF '${CRON} python /opt/crane.py' $CRON_CONFIG_FILE ||echo "${CRON} python /opt/crane.py" >> $CRON_CONFIG_FILE
+grep -qF '@reboot' $CRON_CONFIG_FILE || echo "@reboot python /opt/crane.py" >> $CRON_CONFIG_FILE
 
 exec crond -f
\ No newline at end of file