Hi, 

I have found some instruction no askubuntu. 
Haven't tried that, but you could try to limit the size of syslog and deamon.log in this logrotate file. 

I guess syslog is that big because of node-red, it puts its logs in there. 
You can set the loglevel of node-red to "error" or "fatal" then less is logged. 
Therefore change the loglevel in /home/root/.node-red/settings.js. 

The reason for the deamon.log size would be interesting. 

Another customers was also describing this problem, he did not solve it but used deleting the file with a cron job every certain amount of time as a workaround. 

But for sure it would be better to detect the reason for the big log files.

Best regards!