to rollback only :
Rolled back: 2015_05_15_195423_alter_table_web_directories
php artisan migrate:roll
Best way is to create a new migration and make required changes in that.
Worst case workaround (if you have access to DB plus you are okay with a RESET of that table's data):
your-specific-migration
your-specific-migration
php artisan migrate --path=/database/migrations/your-specific-migration.php
This will force laravel to run that specific migration as no entry about it exists in Laravel's migration history
UPDATE: The Laravel way (Thanks, @thiago-valente)
Run:
php artisan migrate:rollback --path=/database/migrations/your-specific-migration.php
and then:
php artisan migrate
This will re-run that particular migration