Supported Platforms
show spanning-tree bridge
Syntax
Release Information
Command introduced in Junos OS Release 9.0 for EX Series switches.
Description
Display the configured or calculated spanning-tree protocol (can be either STP, RSTP, MSTP, or VSTP) parameters.
Options
none | — | (Optional) Display brief spanning-tree protocol bridge information for all Multiple Spanning Tree Instances (MSTIs). |
brief | detail | — | (Optional) Display the specified level of output. |
msti msti-id | — | (Optional) Display spanning-tree protocol bridge information for the specified MSTI or Common and Internal Spanning Tree (CIST). Specify 0 for CIST. Specify a value from 1 through 4094 for an MSTI. |
vlan vlan-id | — | (Optional) Display spanning-tree protocol bridge information for the specified VLAN. Specify a VLAN tag identifier from 1 through 4094. |
Required Privilege Level
view
List of Sample Output
show spanning-tree bridgeshow spanning-tree bridge brief
show spanning-tree bridge detail
Output Fields
Table 1 lists the output fields for the show spanning-tree bridge command. Output fields are listed in the approximate order in which they appear.
Table 1: show spanning-tree bridge Output Fields
Field Name | Field Description | Level of Output |
|---|---|---|
Context ID | An internally generated identifier. | VSTP all, RSTP all, MSTP all, STP all |
Enabled protocol | Spanning-tree protocol type enabled. | VSTP all, RSTP all, MSTP all, STP all |
Root ID | Bridge ID of the elected spanning tree root bridge. The bridge ID consists of a configurable bridge priority and the MAC address of the bridge. | VSTP all, RSTP all, MSTP all, STP all |
Root cost | Calculated cost to reach the root bridge from the bridge where the command is entered. | VSTP all |
Root port | Interface that is the current elected root port for this bridge. | VSTP all |
CIST regional root | Bridge ID of the elected MSTP regional root bridge. | MSTP all |
CIST internal root cost | Calculated cost to reach the regional root bridge from the bridge where the command is entered. | MSTP all |
Hello time | Configured number of seconds between transmissions of configuration BPDUs. | VSTP all, RSTP all, MSTP all, STP all |
Maximum age | Maximum age of received protocol BPDUs. | VSTP all, RSTP all, MSTP all, STP all |
Forward delay | Configured time an STP bridge port remains in the listening and learning states before transitioning to the forwarding state. | VSTP all, RSTP all, MSTP all, STP all |
Message age | Number of seconds elapsed since the most recent BPDU was received. | VSTP all, RSTP all, STP all |
Number of topology changes | Total number of STP topology changes detected since the switch last booted. | VSTP all, RSTP all, MSTP all, STP all |
Time since last topology change | Number of seconds elapsed since the most recent topology change. | RSTP detail |
Topology change initiator | Interface name of the interface that received the topology change request. | RSTP detail |
Topology change last recvd. from | Bridge ID of the bridge that requested the last topology change. | RSTP detail |
Bridge ID (local) | Locally configured bridge ID. The bridge ID consists of a configurable bridge priority and the MAC address of the bridge. | VSTP all, RSTP all, MSTP all, STP all |
Extended system ID (local) | Internally generated system identifier. | VSTP all, RSTP all, MSTP all, STP all |
MSTI regional root | Bridge ID of the elected MSTP regional root bridge. | MSTP detail |
Internal instance ID (local) | An internally generated identifier. | VSTP all, RSTP all, MSTP all, STP all |
Hello time (local) | Configured number of seconds between transmissions of configuration BPDUs. | RSTP detail, MSTP detail, STP detail |
Maximum age (local) | Maximum age of received protocol BPDUs. | VSTP detail, RSTP detail, MSTP detail, STP detail |
Forward delay (local) | Configured time an STP bridge port remains in the listening and learning states before transitioning to the forwarding state. | RSTP detail, MSTP detail, STP detail |
Path Cost Method (local) | Bridges supporting 802.1D (legacy) implement only 16-bit values for path cost. Newer versions of this standard support 32-bit values. | VSTP detail, RSTP detail, MSTP detail, STP detail |
Maximum Hop count (local) | Configured maximum number of hops a BPDU can be forwarded in the MSTP region. | MSTP detail |
Sample Output
show spanning-tree bridge
user@switch> show spanning-tree bridge STP bridge parameters
Context ID : 0
Enabled protocol : MSTP
STP bridge parameters for CIST
Root ID : 32768.00:11:f2:56:df:40
Root cost : 0
Root port : ge-0/0/1.0
CIST regional root : 32768.00:11:f2:56:df:40
CIST internal root cost : 20000
Hello time : 2 seconds
Maximum age : 20 seconds
Forward delay : 15 seconds
Hop count : 19
Message age : 0
Number of topology changes : 1
Time since last topology change : 108 seconds
Topology change initiator : ge-0/0/1.0
Topology change last recvd. from : 00:11:f2:56:df:4c
Local parameters
Bridge ID : 32768.00:11:f2:57:1c:00
Extended system ID : 0
Internal instance ID : 0
STP bridge parameters for MSTI 10
MSTI regional root : 32778.00:11:f2:56:df:40
Root cost : 20000
Root port : ge-0/0/1.0
Hello time : 2 seconds
Maximum age : 20 seconds
Forward delay : 15 seconds
Hop count : 19
Number of topology changes : 1
Time since last topology change : 108 seconds
Topology change initiator : ge-0/0/1.0
Topology change last recvd. from : 00:11:f2:56:df:41
Local parameters
Bridge ID : 32778.00:11:f2:57:1c:00
Extended system ID : 0
Internal instance ID : 1
show spanning-tree bridge brief
user@switch> show spanning-tree bridge briefSTP bridge parameters
Context ID : 0
Enabled protocol : RSTP
Root ID : 32768.00:19:e2:50:95:a0
Hello time : 2 seconds
Maximum age : 20 seconds
Forward delay : 15 seconds
Message age : 0
Number of topology changes : 0
Local parameters
Bridge ID : 32768.00:19:e2:50:95:a0
Extended system ID : 0
Internal instance ID : 0
show spanning-tree bridge detail
user@switch> show spanning-tree bridge detail
STP bridge parameters
Context ID : 0
Enabled protocol : RSTP
Root ID : 32768.00:19:e2:50:95:a0
Hello time : 2 seconds
Maximum age : 20 seconds
Forward delay : 15 seconds
Message age : 0
Number of topology changes : 0
Local parameters
Bridge ID : 32768.00:19:e2:50:95:a0
Extended system ID : 0
Internal instance ID : 0
Hello time : 2 seconds
Maximum age : 20 seconds
Forward delay : 15 seconds
Path cost method : 32 bit 
