Everything ok in GUI, but two Drive LEDs constantly switch back on

[JCBone]

Hi!

I have a FreeNAS installation with 8x 2TB WD Red Disks. Since yesterday, two Drive Activity LEDs switch back on after disk access. So, on access, all LEDs blink normally (including the two in question), then all LEDs turn off and after a second, both LED switch on - they do not blink, but stay on continuously. There are no problems in the GUI, no smart errors, no warnings, nothing.

What to do? I already switched the position of one drive in the backplane and the lit LED stays with the drive (so it's not the controller or backplane).

Thanks,
Jörg

 

[Morphix]

Hi!

I have a FreeNAS installation with 8x 2TB WD Red Disks. Since yesterday, two Drive Activity LEDs switch back on after disk access. So, on access, all LEDs blink normally (including the two in question), then all LEDs turn off and after a second, both LED switch on - they do not blink, but stay on continuously. There are no problems in the GUI, no smart errors, no warnings, nothing.

What to do? I already switched the position of one drive in the backplane and the lit LED stays with the drive (so it's not the controller or backplane).

Thanks,
Jörg

What controller and backplane?

If the led is moving with the disk, the backplane must be detecting something with the disk.

Sent from my LG-H990 using Tapatalk

 

[JCBone]

Ok, looks like the controller did a verify. After the reboot (to change the drive order, yeah, could have done that on the fly…) it says:

Sep 16 12:12:30 fileserver twa0: INFO: (0x04: 0x0029): Verify started: unit=7
Sep 16 12:12:30 fileserver twa0: INFO: (0x04: 0x0029): Verify started: unit=6
Sep 16 12:18:07 fileserver twa0: INFO: (0x04: 0x002B): Verify completed: unit=7
Sep 16 12:18:23 fileserver twa0: INFO: (0x04: 0x002B): Verify completed: unit=6

Now they stopped beeing lit. Hey, at least that finally made me buy some replacement drives. Two lit LEDs in a RaidZFS2 made me nervous. ;-)

 

[Ericloewe]

Ugh, that's a 3ware controller. Not a good plan and it may be causing your apparently harmless problem, which may actually be masking serious problems with the drive.

I highly recommend moving over to an LSI HBA ASAP.

 

[JCBone]

Ugh, that's a 3ware controller. Not a good plan and it may be causing your apparently harmless problem, which may actually be masking serious problems with the drive.

3ware Controllers mask problems?
Since I only use a controller to be able to hotswap, can I just use the onboard controller? It's not really a problem to shut down the server for maintanance.

 

[Ericloewe]

You don't need an SAS controller for hot swap. Any vaguely usable SATA controller supports that. The determining factors are physical, namely backplane support.

 

[Pezo]

Are there really backplanes in cases with hotswap bays, that don't suppot hotswap?

 

[Ericloewe]

Glad you ask! But first, a short recap of what is needed for safe hot swapping of SATA, SAS and U.2 drives (though an SSD can probably skip all this):

• A backplane connector with three lengths of pins, especially the extra-long pre-charge pins, which are connected to inrush-limiting circuitry inside the drive. Cable SATA power connectors do not have this, their pins are all the same length to reduce complexity.
• Additional capacitance close to the drive (just enough to require electrolytics), to help deal with the inrush current to the drive without excessive voltage drop.

Now, the hall of shame: The Lian-Li PC-Q26: http://www.lian-li.com/en/dt_portfolio/pc-q26/

The backplane it ships with lacks the capacitors it's silkscreened for. It might work, since the connectors used are presumably still appropriate for hot swapping, but it will depend on the power supply.

I don't know if the ones they sell separately are populated with the capacitors, but I'm not going to be the guinea pig for that question.