交換rstpRSTP基本工作原理與STP相同要經(jīng)歷四個(gè)流程也有四

1、RSTP(RapidSTP） 802.1wspanning-treemoderapid-RSTP 中，將接口的鏈路類型分為兩種如查接口工作在全雙工則是point-to-point類型的鏈路注意：僅僅只在點(diǎn)到點(diǎn)鏈路上RSTP才能實(shí)現(xiàn)快速收斂RSTP中定義了3種端口狀態(tài)RSTP AlternatePort：替代端口 Backup Port：備份端口RSTPBPDU的格式Flag8 bit，STP2 bit， RSTP6bitVersion: 2 MessageType:2802.1DSWBPDUBPDU。802.1wSW2SBPDU。TCBPDU，TCBPDURSTPTCconfigBPDU，這樣

2、也實(shí)現(xiàn)了快速收斂RSTPTCN BPDUMST（MultipleSpanningTree） 802.1s CST （Common Spanning Tree）VlanSTPVlanSTPVlan.L2缺點(diǎn)：SWSTP，開銷大。Vlanspanning-treemodemst（spanning-treemstconfiguration name WOLFrevisioninstance1 vlan1-instance2 vlan6-spanning-treemst1priority4096VLANint spanning-treemst1cost19showspanning-treeshowsp

3、anning-treemstshow current show BPDU防護(hù)spanning-treeportfastbpduguarddefault（全局開啟int spanning-treebpduguardenable（接口開啟showspanning-treesummaryShow errdisable recoveryerrdisable recovery cause bpduguard300S（默認(rèn)）bpduguarderrdisableerrdisable recovery interval 30shundown,no shundownBPDU 過濾：不發(fā)也不BPDUSTPBPD

4、UGuard/Filter FBPDUBPDUspanning-treeportfastbpdufilterdefault（全局開啟int spanning-treebpdufilterenable（接口開啟showspanning-treesummaryBPDUBPDU，它將把本端口設(shè)為 blockingBPDU,BPDUint spanning-treeguardshow spanning-tree inconsistentports Showspanning-treeinterfacef0/2detail show spanning-treeDesg P2pLoopguardBPDUlisteninginconsistentinconsistent。spanning-treeloopguarddefault（全局int spanning-treeguardloop（接口UDLDUDLDerr-disable”狀態(tài)。UDLDUDLD15S Sw1(config)#udld enable 也可在接口下配show UDLDUDLD，UDLD8“err-disable”狀態(tài)。Err-disable接口如果進(jìn)入 err-