Drush

There are rare occasions when you want to re-index all your site's content in Solr. Such occasions include:

• Major Drupal version upgrade (e.g. from Drupal 6.x to Drupal 7.x).
• Changing your Solr schema to include more search criteria.
• Upgrading your Solr server to a new major version.
• Moving your Solr server from an old server to a new one.

Everyone needs to have a backup plan for their live site. Not only can your server's disk get corrupted, but you can also erroneously overwrite your site with bad code or bad data, or your site can get hacked. Detecting the latter situations takes some time. Hours or days.

For this reason, you should have multiple backup copies at multiple time points.

The most convenient scheme is to have a 7 day sliding backup: that is, you have one backup snapshot for each day of the week, with today's backup overwriting the backup from 8 days ago.