Nulling out the brokeralert file

Running 4.1.1 and our unix admin wants to copy the broker.alert file every night to a dated backup copy, then null out the existing broker.alert so it only has data for the current day.

Can it be nulled out with the broker running? Any negative impact?

He would probably run one of the two commands below:

echo " " > broker.alert


> broker.alert

Have used cat /dev/null > alert.log with no ill effects.
Had Unix Admin change protections so our EAI support team could do it at will.