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Bridge Domain

Location in GUI: Application Management » Schemas

Diagram
NameTypeConstraintMandatoryDefault Value
bridge_domainsList[bridge_domains]No

NameTypeConstraintMandatoryDefault Value
nameStringRegex: ^[a-zA-Z0-9_.:-]{1,64}$Yes
descriptionStringRegex: ^[a-zA-Z0-9\\!#$%()*,-./:;@ _{|}~?&+]{1,64}$No
l2_unknown_unicastChoiceproxy, floodNoproxy
intersite_bum_trafficBooleantrue, falseNofalse
optimize_wan_bandwidthBooleantrue, falseNofalse
l2_stretchBooleantrue, falseNotrue
unicast_routingBooleantrue, falseNotrue
arp_floodingBooleantrue, falseNofalse
l3_multicastBooleantrue, falseNofalse
virtual_macMACNo
multi_destination_floodingChoicebd-flood, encap-flood, dropNobd-flood
unknown_ipv4_multicastChoiceflood, opt-floodNoflood
unknown_ipv6_multicastChoiceflood, opt-floodNoflood
ep_move_detection_modeChoicegarp, noneNonone
vrfClass[vrf]Yes
subnetsList[subnets]No
sitesList[sites]No
dhcp_policiesList[dhcp_policies]No
dhcp_relay_policyStringRegex: ^[a-zA-Z0-9_.:-]{1,64}$No
dhcp_option_policyStringRegex: ^[a-zA-Z0-9_.:-]{1,64}$No

vrf (ndo.schemas.templates.bridge_domains)

Section titled “vrf (ndo.schemas.templates.bridge_domains)”
NameTypeConstraintMandatoryDefault Value
nameStringRegex: ^[a-zA-Z0-9_.:-]{1,64}$Yes
schemaStringNo
templateStringNo

subnets (ndo.schemas.templates.bridge_domains)

Section titled “subnets (ndo.schemas.templates.bridge_domains)”
NameTypeConstraintMandatoryDefault Value
ipIPYes
scopeChoiceprivate, publicNoprivate
sharedBooleantrue, falseNofalse
no_default_gatewayBooleantrue, falseNofalse
querierBooleantrue, falseNofalse
primaryBooleantrue, falseNofalse

sites (ndo.schemas.templates.bridge_domains)

Section titled “sites (ndo.schemas.templates.bridge_domains)”
NameTypeConstraintMandatoryDefault Value
nameStringYes
advertise_host_routesBooleantrue, falseNofalse
subnetsList[subnets]No
l3outsListString[Regex: ^[a-zA-Z0-9_.:-]{1,64}$]No
macMACNo00:22:BD:F8:19:FF

dhcp_policies (ndo.schemas.templates.bridge_domains)

Section titled “dhcp_policies (ndo.schemas.templates.bridge_domains)”
NameTypeConstraintMandatoryDefault Value
dhcp_relay_policyStringRegex: ^[a-zA-Z0-9_.:-]{1,64}$Yes
dhcp_option_policyStringRegex: ^[a-zA-Z0-9_.:-]{1,64}$No

Example-1: This illustrates a configuration example for a Layer 2 bridge domain named Layer2_BD under Azure Schema/Tenant and Site_A fabric . The unicast_routing flag is set to false, indicating that subnets within this bridge domain are not propagated to the leaf switches, and no routing occurs within the fabric. The l2_unknown_unicast flag is configured to flood, ensuring that unknown unicast traffic is flooded within the bridge domain. The bridge domain is not stretched, as shown by the l2_stretch flag being set to false.

The subnet configuration allows the fabric to manage IP addresses and ARP within the Layer 2 domain without providing routing or default gateway services.

The VRF Prod in this example is defined in a stretched template Site_AB which is further detailed under the vrf section.

ndo:
schemas:
- name: Azure
templates:
- name: Site_A
bridge_domains:
- name: Layer2_BD
l2_unknown_unicast: flood
l2_stretch: false
unicast_routing: false
arp_flooding: true
vrf:
name: PROD
schema: Azure
template: Site_AB
sites:
- name: Site_A
subnets:
- ip: 1.1.1.1/24
scope: public

Example-2: This example illustrates a configuration for a Layer 3 bridge domain named Layer3_BD under Azure Schema/Tenant and Site_A fabric. The default setting for unicast routing is true, so it does not need to be explicitly specified in the YAML. The l2_unknown_unicast flag is set to proxy in this example, which is used to optimize traffic by sending unknown unicast frames to the spine for a proxy lookup in the COOP database. The bridge domain is not stretched, as indicated by the l2_stretch flag set to false.

The EP detection mode is configured as garp, enabling the fabric to detect an endpoint IP move from one MAC address to another when the new MAC is on the same interface and within the same EPG. This mode is often used with VMware ESXi hosts connected to ACI.

The VRF Prod in this example is defined in a stretched template named Site_AB, which is further detailed under the vrf section. To advertise routes externally, an L3Out named Prod_L3out is attached to the bridge domain. Details of the L3Out configuration can be found under the l3out section

ndo:
schemas:
- name: Azure
templates:
- name: Site_A
bridge_domains:
- name: Layer3_BD
l2_unknown_unicast: proxy
l2_stretch: false
arp_flooding: true
ep_move_detection_mode: garp
vrf:
name: PROD
schema: Azure
template: Site_AB
sites:
- name: Site_A
subnets:
- ip: 2.2.2.2/24
scope: public
l3outs:
- Prod_L3OUT