Brocade Communications Systems Brocate Ethernet Access Switch 6910 - Manual (Page 579)

Brocade 6910 Ethernet Access Switch Configuration Guide 529
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CFM Commands
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level-id – Authorized maintenance level for this domain. (Range: 0-7)
type – Specifies the CFM protocol’s creation method for maintenance intermediate points
(MIPs) in this domain:
default – MIPs can be created for any maintenance association (MA) configured in this
domain on any bridge port through which the MA’s VID can pass.
explicit – MIPs can be created for any MA configured in this domain only on bridge
ports through which the MA’s VID can pass, and only if a maintenance end point (MEP)
is created at some lower MA Level.
none – No MIP can be created for any MA configured in this domain.
Default Setting
No maintenance domains are configured.
No MIPs are created for any MA in the specified domain.
Command Mode
Global Configuration
Command Usage
• A domain can only be configured with one name.
• Where domains are nested, an upper-level hierarchical domain must have a higher
maintenance level than the ones it encompasses. The higher to lower level domain types
commonly include entities such as customer, service provider, and operator.
• More than one domain can be configured at the same maintenance level, but a single domain
can only be configured with one maintenance level.
• If MEPs or MAs are configured for a domain using the ethernet cfm mep command or ma index
name command, they must first be removed before you can remove the domain.
• Maintenance domains are designed to provide a transparent method of verifying and resolving
connectivity problems for end-to-end connections. By default, these connections run between
the domain service access points (DSAPs) within each MA defined for a domain, and are
manually configured using the
ethernet cfm mep command.
In contrast, MIPs are interconnection points that make up all possible paths between the
DSAPs within an MA. MIPs are automatically generated by the CFM protocol when the
mip-creation option in this command is set to “default” or “explicit,” and the MIP creation state
machine is invoked (as defined in IEEE 802.1ag). The default option allows MIPs to be created
for all interconnection points within an MA, regardless of the domain’s level in the
maintenance hierarchy (e.g., customer, provider, or operator). While the explicit option only
generates MIPs within an MA if its associated domain is not at the bottom of the maintenance
hierarchy. This option is used to hide the structure of network at the lowest domain level.
The diagnostic functions provided by CFM can be used to detect connectivity failures between
any pair of MEPs in an MA. Using MIPs allows these failures to be isolated to smaller segments
of the network.
Allowing the CFM to generate MIPs exposes more of the network structure to users at higher
domain levels, but can speed up the process of fault detection and recovery. This trade-off
should be carefully considered when designing a CFM maintenance structure.