Issue replacing a bad drive and cross connecting SATA cables.

[Mike_NASBuild]

Hi all - I'm sure this is very simple but ...........

I started getting reports of a drive going bad - so I ordered a new one - went into Pools - hit 'offline' on the bad disk which was device ada3 - noted the serial number - turned off the box - pulled the old drive and put in a new drive.

Now to pull the old drive I had to remove two drive cages - unplug all the SATA cables for all the drives.

replace the drive and replug everything in again.

I have 5 drives - which is one boot and 2 sets of RAID1 mirrors (i.e. 4 drives) the bad drive was on one of my mirror drives.

My question is this ................

Should I have made a note of which SATA cable went which drive ? Because I didn't and I'm wondering if thats causing my problem.

My problem is that when I hit Replace to put the new drive into the RAID .. its coming up with a choice of Member Disk of either ada2 or ada5 and I have no idea which one to pick. I was expecting to see ada3 to replace. So does it matter if I cross-matched my SATA cables and now don't know which cable went to which drive ?

Are the ada designations given by the motherboard - is it noted on the board (ASUS Maximum VIII) which SATA port belongs to which ada number ? I havtn looked because I'm still not sure I'm on the right track even if I do look.

Any insights greatly appreciated!

 

[sretalla]

Are the ada designations given by the motherboard - is it noted on the board (ASUS Maximum VIII) which SATA port belongs to which ada number ?

No, they are not linked in any way that can't vary on each boot.

Should I have made a note of which SATA cable went which drive ? Because I didn't and I'm wondering if thats causing my problem.

My problem is that when I hit Replace to put the new drive into the RAID .. its coming up with a choice of Member Disk of either ada2 or ada5 and I have no idea which one to pick. I was expecting to see ada3 to replace. So does it matter if I cross-matched my SATA cables and now don't know which cable went to which drive ?

No and no.

Also, you don't need to care as those numbers are only for human-readable assistance to identify disks, FreeNAS has it all under control in the background using GPTIDs and GUIDs on the partitions to ensure no matter how a disk is connected, it is associated as the right part of the right pool/VDEV.

If you really need to have numbers aligned for some kind of OCD issue you're having, you can try playing around with cable assignments as it does usually go in order according to the numbering of the ports on the MoBo, but there will never be a guarantee it will work like that every time. Always use serial numbers to identify disks. (available in the Storage - Disks view in the GUI and via a bunch of scripts if you look at the resources section)

 

[artlessknave]

Now to pull the old drive I had to remove two drive cages - unplug all the SATA cables for all the drives.

that sounds....kind of painful
the ada/da designations are assigned by the OS in the order of which drives online first AND order on the controller.
as mentioned above, freenas assumes that will change and uses GPTID, which is in the partition table for each drive and doesn't change.

Show : ada drive order example

say you have only 2 drives on SATAp0 and SATAp2, they will *probably* be ada0 and ada1.

Code:

SATAp0=ada0
SATAp2=ada1

if you then add a hotplug drive on sata1, that will likely be ada2

Code:

SATAp0=ada0
SATAp1=ada2
SATAp2=ada1

until reboot, when everything will realign and be SATAp0=ada0, SATAp1=ada1, SATAp2=ada2

Code:

SATAp0=ada0
SATAp1=ada1
SATAp2=ada2