Replacing a defective drive in a raid5 array in a terrastation TS-8VHL

[teng522]

I have a terrastation ts-8vhl/e with firmware ver. 1.01 in a raid 5 array using 8 3tb barracuda seagate hdd

 

One of the drive gave out and i need to replace it.

 

I shut down the terrastation and replace the drive with a new one but of different model (a seagate sv35 3tb drive)

 

After powering up i got a message that there is an error on array 1.  Operation mode 114, downgrade mode.

 

I went to the system - storage page and proceeded to check and format the new hdd in disk 1 bay.  After formatting, the page said disk 1 is rmm available. However, in the array section, array 1 still indicate error and i don't see rww in parenthesis beside array 1.

 

Clicking on array 1 displayed disk 2 to 8 with the rebuild button dim.

 

I have two questions:

 

1.  How should i replace the defective drive and restore my array with the 8 drives?

 

2.  If i don't have the 8th hdd to replace the damaged one.  How can i rebuild the array using the 7 hdd remaining?

 

Thanks

[teng522]

Thank you Brian.

 

Going back to your suggestion of deleting the array and remade with 7 hdds, will I lose the data in the original array?

 

I will try your suggection of removing the partitions and rebuilding the array afterward first.