Brocade Multi-Service IronWare Administration Guide (Supporting R05.6.00) - Manual (Page 269)

Multi-Service IronWare Administration Guide 251
53-1003028-02
Synthetic loss measurement
6
SYSLOG: <time> Y.1731: The DM session stopped for MA index <ma index>, MD index
<md index>, MEP id <med id> Session index <id>
When the Average delay is greater than the Threshold Average delay.
SYSLOG: <timestamp> Y.1731: The DM session for MA index <ma index>, MD index <md
index>, MEP id <med id> Session index <id> has crossed the forward average
threshold, with value <value>
When the Maximum delay is greater than the Threshold Maximum delay.
SYSLOG: <timestamp> Y.1731: The DM session for MA index <ma index>, MD index <md
index>, MEP id <med id> Session index <id> has crossed the forward maximum
threshold, with value <value>
When the Destination MEP moves to, or is already in a FAILED state, when the session is Active.
<Syslog>: 1DM Session <Id> not started as the RMEP <Id> is in FAILED state.
Synthetic loss measurement
Synthetic loss measurement (SLM) is part of the ITU-T Y.1731 standard. It can be used to
periodically measure Frame Loss, Forward Loss Ratio (FLR), and Frame delay between a pair of
point to point MEPs. Measurements are made between two MEPs belonging to the same domain
and MA.
The procedure involves a Sender MEP sending an SLM Protocol Data Unit (PDU) once per transmit
interval (e.g. 1 second, 10 seconds, 1 minute). The Remote MEP responds with a Synthetic Loss
Reply (SLR). The messages are used to collect the number of SLMs and SLRs transmitted and
received by the two MEPs.
Configuration considerations
• An MEP instance must be configured before configuring Synthetic loss measurement (SLM).
• A Synthetic loss measurement instance cannot be started if the target MEP is not known.
However, the session can start if the remote MEP is known but in a failed state.
• A maximum of 32 SLM sessions can be created per source MEP.
• History data generated after every measurement cycle for a particular SLM session overwrites
the oldest entry after 32 history entries.
• Only one Synthetic loss measurement session will be active per source MEP per COS.
• At any point of time a maximum of 100 SLM sessions can be activated on a node. This number
is shared across all Y1731 modules.
• A maximum of 1000 SLM sessions can be configured over a system. This number is shared
across all Y1731 modules.
• Synthetic loss measurement functionality will not be accurate if VPLS is point to multipoint.
• Synthetic loss measurement support is currently not available for MLX and XMR devices.
• Configuration of tx-interval, measurement interval, threshold, and clear statistics is possible
only under the initiator mode.
• The same set of attributes are available under both the initiator and the responder mode, but
attribute configuration will be rejected if it does not apply for the selected mode.