I have a question I am wondering if someone could help me with. I have 1 2TB HDD in my readynas RN102 2bay server and I want to add a 2nd HHD just to make sure my photos are backed up. Can I use a 500GB HHD, I realize that I am wasting 1.5GB of storage space but I’d rather make sure my data is backed up. I put the 500GB HHD in and it sees it but I do not think that it is doing anything, does it only work if the HHD is on the compatibility list?.

Edited my first response (after I reread your question). What you'll have when you are finished is RAID-1 redundancy - which is not enough to keep your data safe. What you really need to do is make regular backups to another device. If you are doing that already, then RAID-1 gives you a bit more protection and availability during routine disk failures and expansion. To get there from where you are: First you need to back up to a different device. Then you'd need to do a factory reset (which you can do from the web UI), and set up the NAS again, and reload the data from the backup.

The first HHD in there shows that flex-raid is set when I add the second HHD it shows up in the system and it gives me the option of formatting it which I did and still nothing. If the HHD isn't on Netgears compatible list will it not work?

But with raid 1 if one hhd fails the data is still on the other correct? If that happens then I can buy another hhd and then that data would be written to that HHD so it is safe then if yet another hhd fails?

The 2nd disc has to be at least the same capacity as the first disk. Otherwise the NAS will not be able to setup RAID one. As Stephen already pointed out RAID is not a backup. In case of fire, burglery or simply hardware failure to the NAS it self you will still loose your data. RAID will only do some protection againt disc failure.

jmeyer50 wrote: The first HHD in there shows that flex-raid is set when I add the second HHD it shows up in the system and it gives me the option of formatting it which I did and still nothing. If the HHD isn't on Netgears compatible list will it not work? If you are running flexraid, than you can create a second volume on the 500 GB drive. That would be jbod, not RAID-1. That mode is useful if you want to expand capacity, but it does not offer RAID redundancy. With disks off the HCL, you are taking your chances. Many work fine, but some don't. And Netgear can (often will) deny support if you move off the HCL. I recommend NAS-purposed disks (Western Digital "Reds" are what I use myself; many people like the Seagate VN drives). They have better warranties than desktop drives, and aren't as expensive as enterprise. It's often useful to search the forum on the particular model you are considering. I don't recommend Seagate DMs. lundmilo wrote: As Stephen already pointed out RAID is not a backup. In case of fire, burglery or simply hardware failure to the NAS it self you will still loose your data. RAID will only do some protection againt disc failure. Some protection is exactly right. And there are some other failure modes which can also result in data loss (including software failures and unexpected power loss). A lot of posters here have learned the hard way that RAID' redundancy (though useful) is simply not enough. lundmilo wrote: The 2nd disc has to be at least the same capacity as the first disk. Otherwise the NAS will not be able to setup RAID one. Yes - that is why I said you needed to do a factory reset to get to RAID-1. XRAID won't shrink your existing volume down to 500 GB, you need to start again to get to RAID-1. Given the price of new disks, you should consider picking up a WD20EFRX (or the seagate VN equivalent) - then you can just hot-insert the second drive.

Adding a 2nd HHD | NETGEAR Communities

12 Replies

StephenB
Guru
Feb 09, 2016
Edited my first response (after I reread your question).

What you'll have when you are finished is RAID-1 redundancy - which is not enough to keep your data safe. What you really need to do is make regular backups to another device. If you are doing that already, then RAID-1 gives you a bit more protection and availability during routine disk failures and expansion.

To get there from where you are:

First you need to back up to a different device.

Then you'd need to do a factory reset (which you can do from the web UI), and set up the NAS again, and reload the data from the backup.
- jmeyer50
  Aspirant
  Feb 09, 2016
  The first HHD in there shows that flex-raid is set when I add the second HHD it shows up in the system and it gives me the option of formatting it which I did and still nothing. If the HHD isn't on Netgears compatible list will it not work?
  - StephenB
    Guru
    Feb 10, 2016
    jmeyer50 wrote:
    
    The first HHD in there shows that flex-raid is set when I add the second HHD it shows up in the system and it gives me the option of formatting it which I did and still nothing. If the HHD isn't on Netgears compatible list will it not work?
    
    If you are running flexraid, than you can create a second volume on the 500 GB drive. That would be jbod, not RAID-1. That mode is useful if you want to expand capacity, but it does not offer RAID redundancy.
    
    With disks off the HCL, you are taking your chances. Many work fine, but some don't. And Netgear can (often will) deny support if you move off the HCL. I recommend NAS-purposed disks (Western Digital "Reds" are what I use myself; many people like the Seagate VN drives). They have better warranties than desktop drives, and aren't as expensive as enterprise. It's often useful to search the forum on the particular model you are considering. I don't recommend Seagate DMs.
    
    lundmilo wrote:
    
    As Stephen already pointed out RAID is not a backup. In case of fire, burglery or simply hardware failure to the NAS it self you will still loose your data.
    
    RAID will only do some protection againt disc failure.
    
    Some protection is exactly right. And there are some other failure modes which can also result in data loss (including software failures and unexpected power loss). A lot of posters here have learned the hard way that RAID' redundancy (though useful) is simply not enough.
    
    lundmilo wrote:
    
    The 2nd disc has to be at least the same capacity as the first disk. Otherwise the NAS will not be able to setup RAID one.
    
    Yes - that is why I said you needed to do a factory reset to get to RAID-1. XRAID won't shrink your existing volume down to 500 GB, you need to start again to get to RAID-1. Given the price of new disks, you should consider picking up a WD20EFRX (or the seagate VN equivalent) - then you can just hot-insert the second drive.
- jmeyer50
  Aspirant
  Feb 09, 2016
  But with raid 1 if one hhd fails the data is still on the other correct? If that happens then I can buy another hhd and then that data would be written to that HHD so it is safe then if yet another hhd fails?
lundmilo
Luminary
Feb 10, 2016
The 2nd disc has to be at least the same capacity as the first disk. Otherwise the NAS will not be able to setup RAID one.

As Stephen already pointed out RAID is not a backup. In case of fire, burglery or simply hardware failure to the NAS it self you will still loose your data.

RAID will only do some protection againt disc failure.
- jmeyer50
  Aspirant
  Feb 10, 2016
  is it possible to use 2 different size disk? know that the largest capacity would be that of the smaller disk?
  - JennC
    NETGEAR Employee Retired
    Feb 10, 2016
    Hello jmeyer50,
    
    Yes it is possible. But then again, it is recommended you use the same size.
    
    For example, you have 500GB in bay 1 and 1TB in bay 2 and they are configured as XRAID (RAID1) so the volume capacity is just 500GB, you have just wasted the other half of the 1TB in your bay 2.
    
    Regards,