You added a new Brocade VDX 6740 to an existing Brocade VCS Fabric in your data center. You connected the VDX 6740 to ports 3/0/11 and 3/0/12 on the existing fabric. After the switch boots, you realize it does not join the fabric. You examine the ISL status on the fabric as shown in the exhibit.

sw0(conf-if-te-3/0/19)# do sh fabric islport

Name: sw0

Type: 95.2

State: Online

Role: Fabric Principal

VCS Id: 1

Config Mode:Distributed

Rbridge-id: 3

WWN: 10:00:00:05:33:46:71:61

FCF MAC: 00:05:33:46:71:61

Index Interface State Operational State

===================================================================

0 Te 3/0/1 Down

1 Te 3/0/2 Down

2 Te 3/0/3 Down

3 Te 3/0/4 Down

4 Te 3/0/5 Down

5 Te 3/0/6 Down

6 Te 3/0/7 Down

7 Te 3/0/8 Up ISL 10:00:00:05:33:5c:e1:5a "sw0" (downstream)(Trunk Primary)

8 Te 3/0/9 Up ISL (Trunk port, Primary is 3/0/8 )

9 Te 3/0/10 Down

10 Te 3/0/11 Up ISL (Trunk port, Primary is 3/0/12 )

11 Te 3/0/12 Up ISL segmented,(ESC mismatch, Config Mode)(Trunk Primary)

12 Te 3/0/13 Down

13 Te 3/0/14 Down

14 Te 3/0/15 Down

15 Te 3/0/16 Down

16 Te 3/0/17 Down

17 Te 3/0/18 Down

18 Te 3/0/19 Down

19 Te 3/0/20 Down

20 Te 3/0/21 Down

21 Te 3/0/22 Down

22 Te 3/0/23 Down

23 Te 3/0/24 Down

What is causing the problem?