ReadyNAS internal flash/USB

[tigerten]

What is the internal USB and/or flash structure? How does the boot process work? Here is what read from small net builder review abut 626x :

256 MB USB module with Phison USB 3.0 controller and Toshiba TC58NVG1S3HTA00 2Gb NAND flash

Is it the USB is one actually being booted from? The NAND is for storage of firmware, and is not involved in the booting at all?

Appreciate if someone can explain the boot process and function of each component.

If I manage to make an image of the USB part, can I boot a non netgear hardware and convert it to a Readynas?
Thank.

[Sandshark]

The ReadyNAS used syslinux for booting, and the syslinux boot data is on the flash.  But in normal mode, that boot sends it to the OS partition of the drives for the actual booting.  Other modes either put an image from flash into RAM and boot that or boot a USB device.  The flash also contains a default OS image used for an OS re-install.  In the case of a legacy device, the flash also includes the vpd file, which identifies your NAS type and serial number.  None of your personal or configuration data is stored in flash -- it's all on the drives.

[tigerten]

Thanks. It is useful. 

I got the image. It does not work. 

RAIDar shows the NAS status is TFTP_REQ

It was tryin gto extract rot image, but ERROR: could mount boot flash [/dev/null1] no such file or directory

command failed: mdev -s

command failed: /usr/sbin/telnetd

[Sandshark]

Sounds like you need to do a USB recovery: How-do-I-use-the-USB-Recovery-Tool-on-my-ReadyNAS-OS-6-storage-system 

[tigerten]

Sorry I was writing on cellphone. 

my 628x is okay. I made an image of the internal USB and burned the image to USB flash, then boot my PC with that USB. I got the above error. I guess that is because there is no flash drive as a real readynas does. 

[Sandshark]

ReadyNAS OS checks that it is running on Netgear hardware and will not boot on anything else except a VM with very specific limitations.  If you want to study the OS, you are going to need to use Linux tools, not Windows.  I recommend you use a VM, not a real NAS: Creating-an-instance-of-Raidiator-6-10-8-as-a-virtual-machine 

[tigerten]

my Virtualbox mamchine VM has no HDD Gb limitation. Just created 100Gb and works fine. i am sure it can be even bigger. 

Where is that 20 GB limitation from?

[Sandshark]

There may be a limit, but it's certainly not 20GB.  I believe there is also a limit on the number of drives.  I'm not sure where you got that limit from.  Mine is 64GB and I've tested with larger.  I've had plans to try using raw drives, (How-to-use-a-physical-hard-drive-with-a-virtualbox-vm ) mostly to see if it's a viable solution for volume recovery, but I've not put into service the computer I was going to try it on.

[tigerten]

that information re limitation is from the link you provided: 

"The VM emulation on ReadyNAS OS has some restriction for disk size. The maximum size is 20GB. The maximum number of disks is 4. "

None of these are accurate. 

If you are really interested in virtual, headless ESXi is better way to go. You can also run an incidence of xpenology. 

[Sandshark]

Netgear may have failed to continue to include those restrictions in updates to the OS, either intentionally or accidently.

I've never tried ESXi.  VirtualBox is the approved VM platform by my employer, so I have a lot of familiarity with it.  Plus, you are the first to say the ReadyNAS VM will run under it.  I only use the VM for experiments that might brick a real machine before I do it on a real one, so I don't really see a need to switch.  But anyone starting fresh certainly might want to consider it.