Can R730 HDD used on R720?

Without the Dell part number, I can't give a concrete answer, but based on what I could pull using the provided information, it looks like that drive wouldn't have been validated in the R720. It may still work, I would make sure your PERC is up to date first, though.

One of my R720 RAID_1 DISK 1 fails. (no controller stated, there are many as options new and later)

I have couple of R730 in inventory. (some HDD ?) sure they work if empty. (my guess is empty not formatted)

Can I take out R730 HDD and use on R720? (take out, you meant off the spares shelf? or empty in virgin servers never used or formatted.)

I see size is different. R720 is 1TB, R730 HDD is 1.2TB. (oops that can be a problem using small in the larger existing arrays) (the rule is same or larger clearly stated in the RAID controller manual, i cant guess what you have there)

They are both 2.5 inches. Thanks for any answers. sas, 2.5" 10k drives same as all mine here.

the bigger drive installed will have extra unused space and some say you can put small VD there too.

why do that with 200MB IDK,  but could put logs there.

tell goals first then ask how to build it,  best answer come from GOALS now or now + future needs,.

and if home use or small business ,etc.

It will work EXCEPT 1.2TB would be a SAS or SSD size, 1TB would likely be a SATA or NLSAS. You CANNOT mix drive types … you can't mix HDD/SSD, SAS/SATA, etc.

Larger IS fine, however, so long as they are compatible drive types. If you put a larger drive in the array, ONLY the amount that matches the other drives is usable. There is NOTHING you can do with that extra 200GB of space. Nothing.

Assuming the drive types are compatible for the RAID array, just make sure you put the drive in while the server is on … do not power down to introduce hot-swap drives.