Parsing Bootstrap output on the fly?

Question

bash

Good afternoon.
Can you please tell me if it is possible to parse the output of Bootstrap on the fly, so that it throws errors into a separate file?
As soon as I didn’t go out with the script ... But I, however, am not a master yet =)
The line in the script just dumps everything into one file with a common stream:
org.apache.catalina.startup.Bootstrap "[email protected]" start \
>> "$CATALINA_OUT" 2>&1 "&"
And I would like the errors to immediately fly to a separate file.
Thank you.