D-Link DES-3028 Product Manual - Page 136

DES-3028 DES-3028P DES-3028G DES-3052 DES-3052P Layer 2 Fast Ethernet Managed Switch on the Switch. MSTP  Select this parameter to set the Multiple Spanning Tree Protocol (MSTP) globally on the Switch TX Hold Count (1-10) Used to set the maximum number of Hello packets transmitted per interval. The count can be specified from 1 to 10. The default is 6. Forwarding BPDU This field can be Enabled or Disabled. When Enabled, it allows the forwarding of STP BPDU packets from other network devices. The default is Enabled. Loopback Detection This feature is used to temporarily block STP on the Switch when a BPDU packet has been looped back to the switch. When the Switch detects its own BPDU packet coming back, it signifies a loop on the network. STP will automatically be blocked and an alert will be sent to the administrator. The LBD STP port will restart (change to discarding state) when the Loopback Detection Recover Time times out. The user may enable or disable this function using the pull-down menu. LBD Recover Time (0:Disable) This field will set the time the STP port will wait before recovering the STP state set. 0 will denote that the LBD will never time out or restart until the administrator personally changes it. The user may also set a time between 60 and 1000000 seconds. The default is 60 seconds. Click Apply to implement changes made. NOTE: The Hello Time cannot be longer than the Max. Age. Otherwise, a configuration error will occur. Observe the following formulas when setting the above parameters: Max. Age ≤ 2 x (Forward Delay - 1 second) Max. Age ≥ 2 x (Hello Time + 1 second) 122