Specifications

17-26
System Management Software Configuration Guide for Cisco IE 2000U and Connected Grid Switches
Chapter 17 Configuring Ethernet OAM, CFM, and E-LMI
Configuring Y.1731 Fault Management
Ethernet Locked Signal
The Ethernet Locked Signal (ETH-LCK) function communicates the administrative locking of a server
MEP and interruption of data traffic being forwarded to the MEP expecting the traffic. A MEP that
receives frames with ETH-LCK information can differentiate between a defect condition and an
administrative locking. ETH-LCK relies on loopback information (local, remote, port loopback,
per-VLAN loopback, and terminal loopback). The default timer for ETH-LCK is 60 seconds and the
default level is the MIP level.
When a MEP is administratively locked, it sends LCK frames in a direction opposite to its peer MEPs,
based on the LCK transmission period, which is the same as the AIS transmission period. The first LCK
frame is sent immediately following the administrative or diagnostic action.
A MEP receiving a LCK frame verifies that the maintenance level matches its configured maintenance
level, and detects a LCK condition. When no LCK frames are received for an interval of 3.5 times the
LCK transmission period, the MEP clears the LCK condition.
Multicast Ethernet Loopback
The multicast Ethernet loopback (ETH-LB) function verifies bidirectional connectivity of a MEP with
its peer MEPs and is an on-demand OAM function. When the feature is invoked on a MEP by entering
the ping privileged EXEC command, the MEP sends a multicast frame with ETH-LB request
information to peer MEPs in the same MEG. The MEP expects to receive a unicast frame with ETH-LB
reply information from its peer MEPs within a specified time period. A MEP receiving a multicast frame
with ETH-LB request information validates the frame and transmits a frame with reply information.
To configure multicast ETH-LB, you configure the MEG level of the MEP and the priority of the
multicast frames with ETH-LB requests. Multicast frames with ETH-LB request information are always
marked as drop ineligible. No MIP configuration is required.
The MEP sends multicast LB message frames on an on-demand basis. After sending a multicast LBM
frame, the MEP expects to receive LB reply frames within 5 seconds.
When a MEP receives a valid LBM frame, it generates an LB reply frame and sends it to the requested
MEP after a random delay in the range of 0 to 1 second. The validity of the frame is determined on its
having the correct MEG level.
When a MEP sends a multicast LBM frame and receives an LB reply frame within 5 seconds, the LB
reply frame is valid.
Configuring Y.1731 Fault Management
To configure Y.1731 fault management, you must enable CFM and configure MIPs on the participating
interfaces. AIS messages are generated only on interfaces with a configured MIP.
• Default Y.1731 Configuration, page 17-27
• Configuring ETH-AIS, page 17-27
• Configuring ETH-LCK, page 17-29
• Using Multicast Ethernet Loopback, page 17-32