Question What is use for of the secondary port lane of the SAS drive?

[ULTRABYTE]

I would like to applie to PC by SAS SSD using a RAID card.
However, I am concerned about the secondary port(s8~s14 pin out) of SAS SSD.

And I noticed that can used for the 8643 connector of the raid card`s by 1: 4 (single port) and 1: 2 (dual port) cable.
I tried the applied with both cables,
The SSD was recognized as normal and no difference in speed or function could be found.

So I ask.
What is the interface capability of the SAS secondary port (s8 to s14, rx +/- 1, tx +/- 1) and for what reason is it used?
I seek advice from experts.

 

[Andrei N]

The first pic shows the interface capable of supporting both SATA and SAS.
The second and third pics are mini SAS connectors for SAS-3 standard.

 

[kanewolf]

In a rack mounted system with a high-availability configuration, a two cable paths between the controller unit and the drive trays are created and the dual ports are used to support that. When several trays of drives are connected to a single controller, two paths allow all available trays to remain connected to the controller even if one is powered off or fails.

 

[ULTRABYTE]

The first pic shows the interface capable of supporting both SATA and SAS.
The second and third pics are mini SAS connectors for SAS-3 standard.

Thanks for your interest in my activity.