Cisco Nexus 9000 Series - Audience; Document Conventions

Troubleshooting Port-Interface Issues 39
The Interface Configuration Has Disappeared 39
You Cannot Enable an Interface 40
You Cannot Configure a Dedicated Port 40
A Port Remains in a Link Failure or Not Connected State 41
An Unexpected Link Flapping Occurs 41
A Port Is in the ErrDisabled State 42
Verifying the ErrDisable State Using the CLI 43
CHAPTER 6 Troubleshooting vPCs 45
About Troubleshooting vPCs 45
Initial Troubleshooting vPCs Checklist 45
Verifying vPCs Using the CLI 46
Received Type 1 Configuration Element Mismatch 47
Cannot Enable the vPC Feature 48
vPCs in Blocking State 48
VLANs on a vPC Moved to Suspend State 48
Hosts with an HSRP Gateway Cannot Access Beyond Their VLAN 49
CHAPTER 7 Troubleshooting VLANs 51
About Troubleshooting VLANs 51
Guidelines and Limitations for Troubleshooting VLANs 51
Initial Troubleshooting VLANs Checklist 52
Troubleshooting VLAN Issues 53
You Cannot Create a VLAN 53
You Cannot Create a PVLAN 53
The VLAN Interface is Down 53
CHAPTER 8 Troubleshooting STP 55
About Troubleshooting STP 55
Initial Troubleshooting STP Checklist 55
Troubleshooting STP Data Loops 56
Troubleshooting Excessive Packet Flooding 59
Troubleshooting Convergence Time Issues 60
Securing the Network Against Forwarding Loops 60
Cisco Nexus 9000 Series NX-OS Troubleshooting Guide, Release 7.x
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