Should I compress my WD 1TB Black dedicated backup HDD?

WD Internal Drives Desktop & Mobile Drives
1

So my windows 2012 server has an external HDD eSATA Enclosure with 3 - WD Black 6TB HDD, and one WD Black 1TB(formatted in exFAT) HDD used as our backup device for 4-5 clients. We are using VEEAM to send backups to the drive from the clients…that all works great.

There are other programs that we are also sending backup type data to the same drive as well. I also use it to drop important stuff on there from time to time. The External HDD enclosure has no more free slots, and I’d like to keep the backup stuff off the other drives in order to isolate data. I really don’t want to have to upgrade the HDD.
So my question is can/should I compress that drive to save space?
If so, what’s the best type of software to use that could run as a service on the server so that I don’t have to manually invoke compression tasks.

THX.

2

Are your backups not already compressed? If they are, then compressing the drive won’t do much, if anything, to save space.

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The raw backups are from VEEAM, however, i’m also dropping a lot of other files on there that I need secure that aren’t included in the backup image. So there is some data on there that isn’t compressed.