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What VLAN does STP use?
The 802.1Q standard defines one unique Spanning Tree instance to be used by all VLANs in the network. STP runs on the Native VLAN so that it can communicate with both 802.1Q and non-802.1Q compatible switches. This single instance of STP is often referred to as 802.1Q Mono Spanning Tree or Common Spanning Tree (CST).
What is the purpose of STP in a switched VLAN?
Spanning Tree Protocol (STP) is a Layer 2 protocol that runs on bridges and switches. The specification for STP is IEEE 802.1D. The main purpose of STP is to ensure that you do not create loops when you have redundant paths in your network.
What is STP VLAN?
Spanning Tree Protocol (STP) prevents loops in networks and VLAN (Virtual Local Area Network) is used to create many virtual Local Area Networks. STP can be implemented in VLANs. STP puts certain paths into a blocked state (backup links) and the primary links into a forwarding state.
What mode of STP does the port work as normal?
Port states work as normal. When something changes to a port, e.g. it is disconnected/reconnected or shutdown/no shutdown STP will recalculate its algorithm to ensure that there are no loops in the network. It will first place the port that changed into blocking mode, which quickly moves into listening mode.
What is STP and how it works?
STP uses the Spanning-Tree Algorithm (SPA) to create a topology database of the network. To prevent loops, SPA places some interfaces in forwarding state and other interfaces in blocking state. all switches in a network elect a root switch. All working interfaces on the root switch are placed in forwarding state.
What are the common STP port roles?
Those roles include root, designated, alternate, backup, and disabled. Root and designated are still the roles that reach the state of forwarding. The role of Desg and Root port is forwarding traffic. The role of Alt is to block the traffic.
What port does STP use?
Switches with Spanning Tree Protocol implementation in a local area network (LAN). One switch is the STP root bridge. All switch ports that connect a link between two switches are either a root port (RP), a designated port (DP), or a blocked port (BP).
Is STP enabled by default?
STP is enabled by default on devices running Layer 2 code. STP is disabled by default on devices running Layer 3 code. You can enable or disable STP on the following levels: Globally – Affects all ports and port-based VLANs on the device.
What is STP protocol used for?
The Spanning Tree Protocol (STP) is a network protocol that builds a loop-free logical topology for Ethernet networks. The basic function of STP is to prevent bridge loops and the broadcast radiation that results from them.
Can you use VLAN 1 for PAgP and STP?
Having two 3560 switches trunked with 802.1Q, I know Vlan 1 will be used internally by the switches for vtp, pagp, stp traffic. You can’t stop this happening. right? By creating another native vlan say 50 on the trunk, will vlan 50 be use to create stp, vtp information instead of vlan 1.
What happens to VLAN 1 in PVST mode?
In PVST mode, vlan 1 is supposed to interact with IEEE bridges, so vlan 1’s BPDUs are also always sent untagged. However, if vlan 1 is removed from the trunk, no BPDU are sent because the port will not be added to vlan 1’s spanning tree instances.
How to configure Rapid Per VLAN Spanning Tree Protocol?
To configure switches to run the rapid spanning-tree protocol by executing the spanning-tree mode rapid-pvst in global configuration mode as shown below; SW1 con0 is now available Press RETURN to get started. SW1> enable SW1# configure terminal Enter configuration commands, one per line.
Which is the default switch setting in VLAN 1?
Table 3-7 Default Switch Configuration Feature Default Setting Enable state Enabled on VLAN 1 Spanning-tree mode PVST+ (Rapid PVST+ and MSTP are disabled Switch priority 32768 Spanning-tree port priority (configurabl 128