Alcatel-Lucent 7750 Configuration Manual page 158

802.3ah OAM
is not configured, the symbol monitor acts similar to the frame error monitors, requiring manual
intervention to clear a port that has been operationally affected by the monitor. When the optional
signal degrade threshold is configured, it again represents the first level warning. However, it has
an additional function as part of the symbol monitor. If a signal failure event has been raised, the
configured signal degrade threshold becomes the equivalent to a lowering threshold. If a
subsequent window does not reach the configured signal degrade threshold then the previous event
will be cleared and the previously affected port will be returned to service without operator
intervention. This return to service will automatically clear any previously set Information
OAMPDU Flags fields set as a result of the signal failure threshold. The Event Notification
OAMPDU will be generated with the symbol error Link TLV that contains an error count less than
the threshold. This will indicate to the peer that initial problem has been resolved and the port
should be returned to service.
The errored-symbol window is a measure of time that is automatically converted into the number
of symbols for that specific medium for that period of time. The standard MIB entries
"dot3OamErrSymPeriodWindowHi" and "dot3OamErrSymPeriodWindowLo" are marked as
read-only instead of read-write. There is now way to directly configure these values. The
configuration of the window will convert the time and program those two MIB values in an
appropriate manner. Both the configured window and the number of symbols will be displayed
under the show port port-id ethernet efm-oam command.
show port 1/1/1 ethernet efm-oam
===============================================================================
Ethernet Oam (802.3ah)
===============================================================================
Admin State
Oper State
Mode
Pdu Size
Config Revision
Function Support
Transmit Interval
Multiplier
Hold Time
Tunneling
Loop Detected
Grace Tx Enable
No Peer Information Available
Loopback State
Loopback Ignore Rx : Ignore
Ignore Efm State
Link Monitoring
Peer RDI Rx
Critical Event
Dying Gasp
Link Fault
Event Notify
Local SF Action
Event Burst
Page 158
: up
: link fault
: active
: 1518
: 0
: LB
: 1000 ms
: 5
: 0
: false
: false
: true (inactive)
: None
: false
: disabled
: out-of-service
: out-of-service
: out-of-service
: log-only
Discovery
: 1 Ad Link Mon Cap : yes
7750 SR Interface Configuration Guide