You are attempting to merge two Brocade VDX switches, both running in fabric mode, but they segment.

sw0# show fabric islports

Name: sw0

Type: 96.5

State: Online

Role: Fabric Principal

VCS Id: 10

Config Mode:Local-only

Rbridge-id: 4

WWN: 10:00:00:05:33:91:48:f7

FCF MAC: 00:05:33:91:48:f7

sw0# show fabric islports

Name: sw0

Type: 96.5

State: Online

Role: Fabric Principal

VCS Id: 10

Config Mode:Distributed

Rbridge-id: 20

WWN: 10:00:00:05:33:90:92:e4

FCF MAC: 00:05:33:90:92:e4

Referring to the exhibit, what is the reason?