H3C S3100-52P Command Manual

Also see for S3100-52P: Operation manual Operation manual Operation manual Operation manual Operation manual

Contents

Command Manual – MSTPH3C S3100-52P Ethernet Switches Chapter 1 MSTP Configuration Commands1-45A switch removes MAC address entries and ARP entries upon receiving TC-BPDUs. Ifa malicious user sends a large amount of TC-BPDUs to a switch in a short period, theswitch may be busy in removing MAC address entries and ARP entries, which maydecrease the performance of the switch and affect the stability of the network.With the TC-BPDU prevention function enabled, a switch performs only one removingoperation in a specified period (10 seconds by default) after it receives a TC-BPDU.The switch also checks to see whether other TC-BPDUs arrive in this period andperforms another removing operation in the next period if a TC-BPDU is received. Sucha mechanism prevents a switch from being busy in removing MAC address entries andARP entries.Example# Enable the TC-BPDU prevention function on the switch. system-viewSystem View: return to User View with Ctrl+Z.[H3C] stp tc-protection enable1.1.42 stp timer forward-delaySyntaxstp timer forward-delay centi-secondsundo stp timer forward-delayViewSystem viewParametercenti-seconds: Forward delay in centiseconds to be set. This argument ranges from400 to 3,000 and defaults to 1,500.DescriptionUse the stp timer forward-delay command to set the forward delay of the switch.Use the undo stp timer forward-delay command to restore the forward delay to thedefault value.To prevent the occurrence of temporary loops, when a port changes its state fromdiscarding to forwarding, it undergoes an intermediate state and waits for a specificperiod to synchronize with the state transition of the remote switches. This statetransition period is determined by the forward delay configured on the root bridge.The forward delay setting configured on a root bridge applies to all non-root bridges.