Specifications

15-34
Cisco MWR 2941 Mobile Wireless Edge Router Release 3.5 Software Configuration Guide, Cisco IOS Release 15.1(3)MR
OL-26895-01
Chapter 15 Configuring Ethernet OAM, CFM, and E-LMI
Setting Up and Configuring Ethernet OAM
OAM Messages
Ethernet OAM messages or OAM PDUs are standard length, untagged Ethernet frames within the
normal frame length bounds of 64 to 1518 bytes. The maximum OAM PDU frame size exchanged
between two peers is negotiated during the discovery phase.
OAM PDUs always have the destination address of slow protocols (0180.c200.0002) and an Ethertype
of 8809. OAM PDUs do not go beyond a single hop and have a hard-set maximum transmission rate of
10 OAM PDUs per second. Some OAM PDU types may be transmitted multiple times to increase the
likelihood that they will be successfully received on a deteriorating link.
Four types of OAM messages are supported:
• Information OAM PDU—A variable-length OAM PDU that is used for discovery. This OAM PDU
includes local, remote, and organization-specific information.
• Event notification OAM PDU—A variable-length OAM PDU that is used for link monitoring. This
type of OAM PDU may be transmitted multiple times to increase the chance of a successful receipt;
for example, in the case of high-bit errors. Event notification OAM PDUs also may include a time
stamp when generated.
• Loopback control OAM PDU—An OAM PDU fixed at 64 bytes in length that is used to enable or
disable the remote loopback command.
• Vendor-specific OAM PDU—A variable-length OAM PDU that allows the addition of
vendor-specific extensions to OAM.
For instructions on how to configure Ethernet Link OAM, see Setting Up and Configuring Ethernet
OAM, page 15-34.
Setting Up and Configuring Ethernet OAM
This section includes this information:
• Default Ethernet OAM Configuration, page 15-34
• Ethernet OAM Configuration Guidelines, page 15-35
• Enabling Ethernet OAM on an Interface, page 15-35
• Enabling Ethernet OAM Remote Loopback, page 15-36
• Configuring Ethernet OAM Link Monitoring, page 15-36
• Configuring Ethernet OAM Remote Failure Indications, page 15-40
• Configuring Ethernet OAM Templates, page 15-40
Default Ethernet OAM Configuration
Ethernet OAM is disabled on all interfaces.
When Ethernet OAM is enabled on an interface, link monitoring is automatically turned on.
Remote loopback is disabled.
No Ethernet OAM templates are configured.