ACMIB :: bridgeDomainDesignatedRoot

MIB Reference — IPNetwork Monitor · Updated September 14, 2026

All MIBsACMIBbridgeDomainDesignatedRoot

bridgeDomainDesignatedRoot

Module: ACMIB

OID (symbolic): ACMIB::bridgeDomainDesignatedRoot

OID (numeric): 1.3.6.1.4.1.1751.2.18.5.9.1.6

Node type: OBJECT-TYPE

Type: OCTET STRING

Access: read-only

Description: The bridge identifier of the root of the spanning tree as determined by the Spanning Tree Protocol as executed by this node. This value is used as the Root Identifier parameter in all Configuration Bridge PDUs originated by this node.

What is bridgeDomainDesignatedRoot?

This OID stores the 6-byte MAC address of whichever bridge the spanning tree protocol identified as the network root. Engineers consult this to verify that the correct switch is serving as the spanning tree root and to detect unexpected root changes that could indicate network instability. For example, a MAC address of '00:11:22:33:44:55' identifies which physical device is controlling the topology.

Examples

Walk all instances (SNMPv2c):

snmpwalk -v2c -c public <target> 1.3.6.1.4.1.1751.2.18.5.9.1.6
snmpwalk -v2c -c public <target> ACMIB::bridgeDomainDesignatedRoot

Get a specific instance (index 1):

snmpget -v2c -c public <target> 1.3.6.1.4.1.1751.2.18.5.9.1.6.1
snmpget -v2c -c public <target> ACMIB::bridgeDomainDesignatedRoot.1

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OID Breakdown

Upper-level ancestors (6 from the standard OID tree / other modules)
Numeric OIDNameModule
1isoLANART-AGENT
1.3orgAirPair-MIB
1.3.6dodAirPair-MIB
1.3.6.1internetAirPair-MIB
1.3.6.1.4privateAirPair-MIB
1.3.6.1.4.1enterprisesAirPair-MIB
Numeric OIDNameModule
1.3.6.1.4.1.1751lucentACMIB
1.3.6.1.4.1.1751.2mibsACMIB
1.3.6.1.4.1.1751.2.18acMIBACMIB
1.3.6.1.4.1.1751.2.18.5intfConfigACMIB
1.3.6.1.4.1.1751.2.18.5.9bridgeDomainTableACMIB
1.3.6.1.4.1.1751.2.18.5.9.1bridgeDomainEntryACMIB
1.3.6.1.4.1.1751.2.18.5.9.1.6bridgeDomainDesignatedRootACMIB