Interface Configuration
7210 SAS M, T, X, R6, R12, Mxp, S, Sx Interface Configuration Guide Page 111
802.3ah OAM
802.3ah Clause 57 (EFM OAM) defines the Operations, Administration, and Maintenance (OAM)
sub-layer, which provides mechanisms useful for monitoring link operation such as remote fault
indication and remote loopback control. In general, OAM provides network operators the ability
to monitor the health of the network and quickly determine the location of failing links or fault
conditions. EFM OAM described in this clause provides data link layer mechanisms that
complement applications that may reside in higher layers.
OAM information is conveyed in slow protocol frames called OAM protocol data units
(OAMPDUs). OAMPDUs contain the appropriate control and status information used to monitor,
test and troubleshoot OAM-enabled links. OAMPDUs traverse a single link, being passed
between peer OAM entities, and as such, are not forwarded by MAC clients (like bridges or
switches).
The following EFM OAM functions are supported:
• EFM OAM capability discovery.
• Active and passive modes.
• Remote failure indication — Handling of critical link events (for example, link fault,
dying gasp)
• Loopback — A mechanism is provided to support a data link layer frame-level loopback
mode. Both remote and local loopback modes are supported.
• Dying Gasp support on 7210 SAS platforms:
− 7210 SAS-X, 7210 SAS-M, 7210 SAS-T, 7210 SAS-Sx/S 1/10GE, and 7210 SAS-Sx
10/100GE generate EFM OAM dying gasp messages on loss of power. EFM OAM
dying gasp messages are generated on either Network ports or Access uplink ports
based on the mode in which the device is operating. They are not generated on access
ports. These platforms also support generation of SNMP dying gasp messages on
power failure and it is mutually exclusive to generation of EFM OAM dying gasp
messages. Please see the System Management guide for more information about
support for SNMP dying gasp.
− 7210 SAS-R6 and 7210 SAS-R12 devices do not generate SNMP or EFM OAM
dying gasp.
− All 7210 SAS platforms, process the received EFM OAM dying gasp, on a port
enabled for EFM and generate a SNMP trap.
• EFM OAMPDU tunneling.
• High resolution timer for EFM OAM in 500ms interval (minimum).