Magento: Run index management from command line

First, go to the directory MagentoRoot/shell

cd $MageROOT/shell

Get the status of reindexing processes

php indexer.php --status

To reindex all indexes.

php indexer.php --reindexall

To reindex individual index one by one

php indexer.php --reindex catalog_product_attribute #Product Attributes
php indexer.php --reindex catalog_product_price 	#Product Prices
php indexer.php --reindex catalog_url 				#Catalog Url Rewrites
php indexer.php --reindex catalog_product_flat 		#Product Flat Data
php indexer.php --reindex catalog_category_flat 	#Category Flat Data
php indexer.php --reindex catalog_category_product 	#Category Products
php indexer.php --reindex catalogsearch_fulltext 	#Catalog Search Index
php indexer.php --reindex cataloginventory_stock	#Stock Status

These reindex can also be scheduled to run as a cron job.