Problem setting up Netbackup SSO (Shared Storage Options)

Thanks for the output.

Firstly, we see that stu ESL025_EBS6_MPX  is configured for 4 drives:

Label:                ESL025_EBS6_MPX
Storage Unit Type:    Media Manager
Host Connection:      ebs6-bck
Number of Drives:     4
On Demand Only:       no
Max MPX/drive:        12
Density:              hcart2 - 1/2 Inch Cartridge 2
Robot Type/Number:    TLD / 1
Max Fragment Size:    1048575 MB

Why is that when only 2 drives are assigned to this media server on this host?

As I have said before, this will result in over-allocation of jobs for this STU.

Can you confirm that SSO license key was added to both of these media servers? (Check output of get_license_key on both media servers).

vmoprcmd tells us that NBU was probably not restarted on media server ebs7 after drives were configured as SSO?

ESL025_Drive12           No      No                     No        hcart2
    ebs6-bck                   /dev/rmt/1cbn                        SCAN-TLD
    ebs7-bck                   /dev/rmt1.1                          RESTART

NBU needs to be restarted on both media servers.

Please correct the STU config on the master server and run 'bprdreq -rereadconfig'.

If above steps were taken and drive 12 is still not used, try to down drive 11 on ebs6 and see if drive 12 gets used.

Let us know the result.