We encountered a really great problem (at least for our company, but I think many companies might get this issue too in the nearest future).
We have an O365 Tenant and Veeam Backup for Office 365. Our company currently migrates all mail-items from our Postfix servers to Exchange Online. We aren’t using any third party software, only the standard Exchange Online migration tool. We have migrated almost 4Tb of mail items by now, totally we have 20Tb of mail.
The problem is that the most part of our mails is copied/backed up only to Database named “2018”.
Our VBO Server is a virtual Windows Server 2012. The only working service is VBO. We have only one simple backup task – backup all except 3 mailboxes. We have only one directly attached disk, most of it allocated as a repository for VBO. In the root folder of repository, VBO created many child folders naming from 2005 to 2018, containing database files, logs and others. I thought these folders were equivalent to mail-items receive date and that’s might be good for us in the future (for example, we could copy these folders and database to another disk for archive, or backup it to tapes and enable retention policy). But most of these folders (from “2005” to “2017”) occupy 35Gb only, and the folder named “2018” occupies 3,7Tb. And this is a problem. We have a very huge backup database and it is growing and we can’t do anything with this. Making many repositories is not a solution – we have almost 1500 employees in our company, and creating many backup tasks for equable disk space utilization in various repositories would cause a lot of inconvenience and routine work. Furthermore, this will entail continuous backup to tapes – at the beginning we planned to make only one time backup to tape of all old mail for archive.
I created a Support Ticket (Case # 02974722) with this issue, and after some logs searches, the support engineer told me, that the problem is that VBO checks attribute “last_modified_date” for items. So, if we migrate all our mail in 2018 year – all of our mail items will have “last_modified_date”=2018. It’s terrible! And it doesn’t answer the question – why does VBO create many folders in the root folder, if it doesn’t backup mail items to these folders? Can you add another parameter for checking message date in the nearest future? Or maybe you could make patch, or script for the database fix? I think, many companies, that have mail for last 10-15 years, might get the same issue. We really need it fixed – keeping all mails in one folder regardless of their date is fundamentally wrong and might cause serious problems in future. Furthermore, using 20Tb of disk space is too expensive, especially when you have many tapes for this purpose.