I tried, unsuccessfully, two ways to archive a course:
1) through the admin course
2) through file manager as a professor in the course itself.
Both ways failed with the error:
An error occured while archiving the course testcourse101:Failed to archive course directory '/opt/webwork/courses/testcourse101' with command '2>&1 /bin/tar -C /opt/webwork/courses/testcourse101/.. -czf '/opt/webwork/courses/ 02b3c920-2d65-11e5-a34e-f36c32199daf_testcourse101.tar.gz' testcourse101' (exit=72057594037927935 signal=127 core=128): at /opt/webwork/webwork2/lib/WeBWorK/ContentGenerator/CourseAdmin.pm line 1858.
plus a whole list of warning messages that began with:
Use of uninitialized value $dump_out in concatenation (.) or string at /opt/webwork/webwork2/lib/WeBWorK/DB/Schema/NewSQL/Std.pm line 233.
Warning: Failed to dump table 'testcourse101_key' with command '2>&1 /usr/bin/mysqldump --defaults-file=/tmp/tZYRISziXn webwork testcourse101_key > /opt/webwork/courses/testcourse101/DATA/mysqldump/key.sql' (exit=72057594037927935 signal=127 core=128):
This can be expected if the course was created with an earlier version of WeBWorK. at /opt/webwork/webwork2/lib/WeBWorK/DB/Schema/NewSQL/Std.pm line 234.
I also tried Upgrade Course before doing the archive but that didn't help.