December 9, 1998
After a Y-Redundant switch-over on an ASI card set, traffic experiences excessive delays on available bit rate (ABR) connections, and QBin full-discards on constant bit rate (CBR) connections.
This problem is a result of the stand-by card of an ASI Y-Redundant pair not being programmed correctly prior to a Y-Redundant switch.
Switching to Y-Redundant backup causes the connection's performance to be reduced. The problem manifests itself as excess delay on ABR connections, to discards due to Qbin full and Tx EFCI cells on CBR connections.
With ABR connections, the delay seen by the end device increases from 200msec to approximately 2 seconds. With CBR connections, the Qbin full-discards. To get out of this condition, delete Y-Redundant and reset the cards.
The following procedure should be performed on all stand-by cards of ASI Y-Redundant pairs to ensure that they are programmed correctly prior to a Y-Redundant switch. This procedure must be performed on stand-by ASI cards after an addyred, resetcd slot of a stand-by ASI card or insertion of a stand-by ASI card. This procedure does not need to be performed following a switchcc. You must have Service level access or higher to perform this procedure.
Build the following control packet:
The UI will prompt "Enter Function Code". Enter 4.
The UI will prompt "Enter Operator Code". Enter 0.
The UI will prompt "Enter Data Byte 0". Enter . This terminates the packet.
Down the card by entering:
Send the control packet by entering:
xcp1 slot 1
The UI should display an acknowledgement message. If not, send the control packet again.
Up the card by entering:
Because this workaround activates the stand-by card, the active LED on the front panel of the stand-by card will be green, making it difficult to distinguish which card of the Y-Redundant pair is active. In other words, the active LED on the active and standby cards will both be green.
For More Information
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