Document backups

[hackartisan]

• Where primary and secondary backups live
• What to do if you need a restore

[acozine]

Related to #193. But we should also cover MariaDB backups, Solr backups, and anything else we back up and might need to restore.

[Himanshusoni9]

One More issue : On Solr Collection Data Backup Based on Condition/Data Filter.(There is no provision for that . )

Because SOLR BACKUP API with Query is not working
//http://localhost:8983/solr/admin/collections?action=RESTORE&name=myBackupName&location=C:\Users\DELL\Downloads\SOLR_BACKUP&collection=myCondCollection&query=text:cellphone

I am trying out to perform backups of our Solr data with a particular condition in mind.

To provide some context, let's say Solr collection consists of 100 records, among which 70 records contain the text "mobile," and the remaining 30 records contain the text "cellphone." my objective is to take a Solr collection/data backup that contains only the records the text "cellphone" – essentially, we want to create a backup file that reflects these 30 specific records only.

I would greatly appreciate it if you could share insights on the best practices or methods to achieve this selective backup based on a condition. If there are specific parameters or commands we should be utilizing, kindly provide the necessary guidance. Additionally, any documentation or references you could point us to would be immensely helpful.

Thank you in advance for your time and assistance. We value your expertise and look forward to implementing an efficient solution based on your recommendations.