What to do when DSA 2800 is unable to detect the expansion unit?

Question

What to do when DSA 2800 is unable to detect the expansion unit?

System:

Dual controller 12x12TB and one expansion unit 8x12TB

Issue: 

When you access the DSA via web browser by entering the IP address of the management port, you are not able to see the expansions in the Hardware tab. You only see the controller.

Also, when you add the DSA in the VRM pool, the storage capacity is less than it is supposed to.

Answer

• Please make sure that the cable is inserted correctly. 

• Please reseat (pull out and plug-in back) the SAS cables connecting both controllers and the drive extension.

• Please check if there is any LED activity on the connected ports (see pages 14-16 from the below manual):
  https://resources-boschsecurity-cdn.azureedge.net/public/documents/DSA_E_Series_Installation_Manual_enUS_42248574603.pdf

Note: 

In case there are multiple expansion units or a single controller, please follow the Installation Manual (starting with page 23) to see how the connections should be done.

If you still cannot detect the expansion unit, please provide the Technical Support Team with the following details:

1. Which is the part number of the DSA E2800 controller unit? E.g.: DSA-N2xxxx-xxxx
2. Which is the part number of the DSA E2800 expansion unit? E.g.: DSX-N1xxxx-xxxx

3. How many expansion units did you add?

4. Which is the serial number of the controller? Please give us the NetApp serial number. It should start with 72... and it should have 12 characters.
5. Please fill in the registration form: https://resources-boschsecurity-cdn.azureedge.net/public/documents/Registration_DIP_600_Special_enUS_9007222920871435.docx
6. What happened that made you conclude that the expansion unit is not detected? Where exactly did you notice these issues?
7. Since when did the issue start to appear? 
8. Did this ever work before?
9. Check if the IOM (SAS) ports on controllers and the drive extension show any connectivity or other indication and write down your findings.
10. Collect the support bundle file. The instructions can be found here: https://community.boschsecurity.com/t5/Security-Video/How-to-download-the-support-bundle-file-for-DSA-E-Series-E2800/ta-p/16724
11. Have you configured the DSA before connecting the expansion unit? 
12. Is the link up on the SFP? If the LED is on, which is the color? Is it flashing? 
13. Could you please take some pictures with the connections on the back? 
14. Would it be possible to do a video when you restart the DSA? 
15. What type of SAS-cables are used for Controller-to-Extension connection: SAS-2 or SAS-3, HD or non-HD?:
16. Who is the vendor of the cables?
17. Are the cables in the original equipment of the drive extension?:
18. Please provide Part Number (P/N) of the cables used.

Useful:

• How to add expansion shelf to NetApp DSA E-Series E2600 & E2700 & E2800 Base?

•  Other useful resource