## Installation

### parallel installation

by Nandor Sieben -
Number of replies: 0
It was time at NAU to update our webwork server. We purchased two machines and try to make them work balanced. Both machines run webwork. A balancing machine assign one of the machines for every student trying to access webwork. So students get one or the other randomly. The database server is running on a separate machine. The courses directory is on a shared filesystem. The rest is separate on both machines. Is this good enough, are there any other directories that needs to go on the shared filesystem? In particular I have the following warning on one of the machines but not on the other:
• cd /usr/local/webwork2/tmp/ImageGenerator.p9xZLSub && /bin/mv /usr/local/webwork2/tmp/ImageGenerator.p9xZLSub/equation1.png /usr/local/webwork2/htdocs/tmp/equations/b0/e9a9e7e3cd6ba1004badd4d33c20291.png returned non-zero status 256: Bad file descriptor at /usr/local/pg/lib/WeBWorK/PG/ImageGenerator.pm line 403.
• cd /usr/local/webwork2/tmp/ImageGenerator.p9xZLSub && /bin/mv /usr/local/webwork2/tmp/ImageGenerator.p9xZLSub/equation2.png /usr/local/webwork2/htdocs/tmp/equations/b0/e9a9e7e3cd6ba1004badd4d33c20291.png returned non-zero status 256: Bad file descriptor at /usr/local/pg/lib/WeBWorK/PG/ImageGenerator.pm line 403.
Is it possible that some kind of info is stored about the available images on the database server and both machines think the same images are available but in fact the machines have different images available?

Nandor