I have the following cron job in DreamHost which runs Test1.php and writes to Test2.php:
/usr/bin/php /home/Test15/Web/Test1.php>
/home/Test15/Web/Test2.php 2>&1
How can I make this write to a second file?
Have your Test1.php use fopen or file_put_contents to write to a second file.
You can use use the command tee. Type in the shell man tee for more information. In you case, if we assume the second file is here /home/Test15/Web/Test3.php, you can use that:
/usr/bin/php /home/Test15/Web/Test1.php | tee /home/Test15/Web/Test2.php /home/Test15/Web/Test3.php
That should redirect the output to both files.