Bridge id priority 49162 priority 49152 sysidext 10 address 000f. Like it name, rstp rapid spanning tree protocol is the fastest converged version of stp. For an ethernet network to function properly, only one active. Cisco ccna rapid spanning tree protocol rstp configuration. In rstp, link status of each port are monitored proactively instead of waiting for the bpdu messages to detect network topology changes. Only the root bridge generated bpdus in the classic spanningtree and those were relayed by the nonroot switches if they received it on their root port. You can download the cisco packet tracer example with.
Understanding spanning tree protocols stp, rstp, mstp. The transmitting switch port id, will be discussed later 2. Rapid spanning tree protocol rstp provides faster topology convergence. Ccna training rapid spanning tree protocol rstp tutorial. Election of designated port rstp port roles root port. Switches running stp will build a map or topology of the entire switching network.
First, it prevents problems caused by loops on a network. Can i run my cisco switch on rpvst and non cisco switch on ieee 802. Mar 18, 20 cisco icnd2 configure, verify, and troubleshoot rstp operation february 12, 20 march 18, 20 chris stark cisco, icnd2 this topic will cover configuring, verifying and troubleshooting the rapid spanning tree protocol. Dell networking and cisco spanning tree interoperability. Stp spanning tree protocol automatically removes layer 2 switching loops by shutting down the redundant links. Cisco icnd2 configure, verify, and troubleshoot rstp operation february 12, 20 march 18, 20 chris stark cisco, icnd2 this topic will cover configuring, verifying and troubleshooting the rapid spanning tree protocol. Spanning tree protocol amstp for optical ethernet backbones pdf. Introducing rapid spanning tree protocol chapter 10. We are calculating a rapid spanning tree for each vlan. Switches might also learn endstation mac addresses on multiple layer 2 interfaces. Root port is the port that is closest to the root bridge, which means it is the port that receiving the lowestcost bpdu from the root every nonroot bridge must have a root port. Spanning tree protocol in layer 2layer 3 environments.
This table shows the support for mst in various catalyst switches. An example of how to configure a simple, three switch mstp topology. Introduction this document provides information about the enhancements added by rstp to the previous 802. Rstp provides significantly faster spanning tree convergence after a topology change, introducing new convergence behaviors and bridge port roles to do this. Additional features are available on highend cisco bridges, such as 6500, to limit. Cisco has several documents about how to interoperate with non cisco switches e. The real difference lies in the role the spanning tree assigns to the port. Spanning tree also allows a network design to include spare redundant links to provide automatic backup paths if an active link fails. Stp spanning tree protocol explained with examples. The spanning tree protocol stp is a network protocol that builds a loopfree logical topology in, the ieee introduced rapid spanning tree protocol rstp as w. The version field in legacy stp was set at 1, but in rstp, the version is set at 2. In this section, you will learn how different varieties of spanningtree.
The major advantage of rstp is that switches use bpdu frames differently than before. The spanning tree protocol stp is a network protocol that builds a loopfree logical topology for ethernet networks. Before reading this article you should understand how stp works. In cisco implementation, discarding is replaced with blocking. The root path cost is used to elect root port and we will discuss in the next part. Stp spanning tree protocol step by step configuration. Nowadays it is a popular solution to implement redundant networks in critical systems for energy, aerospace or factory automation. In this example, we will configure rstp rapid spanning tree protocol with packet tracer.
Lets walk through the other stuff that has been changed. Spanning tree stprstp interoperability of ex switches with. Spanning tree protocol stp and its much more recent update, the rapid. Stp will identify if there are any loops, and then disable or block.
Nov 04, 2010 understanding the nuts and bolts of the rstp operation is beyond the scope of this tutorial. A redundant link is usually created for backup purposes. Spanning tree protocol stp spanning tree protocol stp was developed to prevent the broadcast storms caused by switching loops. It has some similarities with cisco systems multiple instances spanning tree. Understanding multiple spanning tree protocol, or how to convert the cisco switches to mst e. A redundant link is an additional link between two switches. The basic function of stp is to prevent bridge loops and the broadcast radiation that results from them. Rapid spanningtree protocol in cisco packet tracer. Rapid spanning tree protocol improved stp with faster convergence backward compatible with stp rstp ieee 802. Rapid spanning tree protocol rstp one big disadvantage of stp is the low convergence which is very important in switched network. Both discard frames and do not learn mac addresses. The basic function of stp is to prevent bridge loops and ensuing broadcast radiation. For example, in the following scenario, the upstream cisco switch influences path choice due to its lower advertised cost to reach the root bridge.
Rapid spanning tree protocol per vlan spanning tree. Thats itjust one command will enable rapid spanning tree on our switches. Aug 28, 2011 in this video jagvinder thind shows rstp configuration in hindi or rapid spanning tree protocol 802. Spanning tree protocol stp was developed before switches were created in order to deal with an issue that occurred with networks that were implementing network bridges. Rstp was designed to be backwardscompatible with standard stp. The bridges send configuration bpdus through the ethernet and radio ports. Since rstp only has single spanning tree instance for all vlans across a trunk and there is no vlan awareness, all traffic will be forwarded or blocked based.
Election of root bridge and same tiebreaking criteria 2. When edge port goes updown, there is no significant topology change. Understanding spanning tree protocol 3 cisco 3200 series wireless mic software configuration guide when the bridges in a network are powered up, each br idge functions as the stp root. While spanning tree stp takes more than 30 seconds to move a port to a forwarding state, rstp can move a port to the forwarding state within 3 times of the hello interval the default hello interval is 2 seconds. Rapid spanningtree has a way of dealing with switches running the older spanningtree version. The stp terms are explained and exemplified with this example network. Spanning tree stprstp interoperability of ex switches. Apr 16, 2011 so, rapid spanning tree protocol rstp was conceived to overcome this problem rstp takes 56 seconds to update and reconfigure the new network topology routes. If a link fails, stp and rstp automatically establishes a new loopfree topology. Second, when redundant loops are planned on a network, stp deals with remediation of network. Spanning tree also allows a network design to include backup links providing fault tolerance if an active link fails as the name suggests, stp creates a spanning tree that. Similar to legacy st, prstp implements a single instance of spanning tree but dramatically improves the convergence time. Download pdf stp spanning tree protocol step by step configuration tutorial when sw3 start receiving inferior bpdus at its interface from sw2, switch3 would ignore the inferior information until the bpdus stored with the blocked port expires max age timer 20 seconds. For example, switchc will receive a bpdu with a path cost of 0 from.
For example, consider the decision of how to handle traffic forwarding over. So if you are not sure about stp, please read my article about spanning tree protocol tutorial first. On the cisco devices, the command spanningtree pathcost method long must be entered to make it compliant with ieee stp path cost. The best dollar youve ever spent on your cisco career. Stp is enabled by default on all cisco switches, for all vlans. For example, lets say a switch has 2 paths to the rootbridge, it will. Introducing rapid spanning tree protocol etutorials. In this video jagvinder thind shows rstp configuration in hindi or rapid spanning tree protocol 802. Election of root port on nonroot with the same rules 3. Before we begin with rstp rapid spanning tree protocol, we should. Multiple spanning tree mst is an ieee standard inspired from the cisco proprietary multiple instances spanning tree protocol mistp implementation. Cisco has several documents about how to interoperate with noncisco switches e. Most parameters have been left unchanged so users familiar with 802. There are also a lot of other documents about this subject, which you will find if you do a.
For purposes of this document, as implemented by the ieee 802. The multiple spanning tree protocol mstp and algorithm, provides both simple and full. Understanding the nuts and bolts of the rstp operation is beyond the scope of this tutorial. Spanningtree protocol is a link management protocol that provides path redundancy while preventing undesirable loops in the network. All you need to know at this stage is the terminology and benefits of using it over a legacy stp.
To overcome this problem, in 2001, the ieee with document 802. The third device can be a cisco nexus 2000 series fabric extender or a switch, server, or any other networking device. The implementation of rapid spanning tree is rapidpvst. Spanning tree enabled protocol rstp root id priority 24586 address 0015.
The spanning tree protocol stp is a network protocol that ensures a loopfree topology for any bridged ethernet local area network. Rapid spanning tree protocol rstp ieee defined an improved version of stp in standard 802. Juniper networks qfx series products use rapid spanning tree protocol rstp on the network side of the qfx series to provide quicker convergence time than the base spanning tree protocol stp does. This document assumes that the reader is familiar with rapid stp rstp 802. Just like every coin has two sides, a redundant link, along with several advantages, has some disadvantages. Rapid spanning tree protocol rstp, which significantly reduces the convergence time after a. Vlan, trunking, vtp, stp, rstp, switch security and. Spanning tree protocol interoperability with cisco arista networks. Rstp is similar to stp, but is designed for more rapid failover, on the order of several seconds rather than up to 45 seconds to restabilization. With the advent of layer 3 switching in lan environments, bridging now competes with. So, rapid spanning tree protocol rstp was conceived to overcome this problem rstp takes 56 seconds to update and reconfigure the new network topology routes. Cisco vpc a virtual portchannel vpc allows links that are physically connected to two different cisco nexus 5000 series devices to appear as a single port channel to a third device. Aug 04, 2011 rapid spanning tree protocol rstp in 2001, the ieee introduced rapid spanning tree protocol rstp as 802. This document provides information about the enhancements added by rstp to the previous 802.
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