...indexing via GUI fails and status is "processing"...?

> cd index
> php -f indexer.php -- --reindex catalog_url

...gives error messages that should help.

see database for possible indexing identifiers:
mysql> use magento;
mysql> select * from index_process;


magento version:
1.6.1.0

date:
Thu Dec 8 01:12:43 CET 2011

sources:
http://rackspeed.de/forum/magento-faq-backend/there-a-problem-with-reindexing-process-582