Revised July 10, 2007
April 12, 2000
NOTICE:
THIS FIELD NOTICE HAS BEEN ARCHIVED AND IS NO LONGER MAINTAINED OR UPDATED BY CISCO.
THIS FIELD NOTICE IS PROVIDED ON AN "AS IS" BASIS AND DOES NOT IMPLY ANY KIND OF GUARANTEE, WARRANTY OR SUPPORT. USE OF THE INFORMATION ON THIS FIELD NOTICE OR MATERIALS LINKED FROM THIS FIELD NOTICE IS AT YOUR OWN RISK. CISCO RESERVES THE RIGHT TO CHANGE OR UPDATE THIS FIELD NOTICE AT ANY TIME.
Products Affected
|
Product |
Comments |
|---|---|
|
Cisco ONS 15454 |
Formerly Cerent 454 |
Problem Description
Deleting a Virtual Tributary (VT) 1.5 level circuit or deleting 1+1 protection groups could affect circuits provisioned on slot 1.
The Cerent 454 encapsulates an external signal into a Synchronous Transport Signal (STS) payload on the associated card. Within an STS are 28 Virtual Tributaries (VTs). A VT is equivalent to a T1, and an STS is equivalent to OC1. An XC is a Cross Connect card and an XCVT is a Cross Connect with Virtual Tributary capability.
For example, on an DS3-12 card, the card has 12 STS payloads that are fed to the XCVT for routing in the appropriate direction. The DS3s are inserted and extracted from these STS signals on the DS3-12 card.
Background
This problem was discovered during testing in the Cerent System Verification Lab.
Problem Symptoms
The following actions could cause service to be affected on circuits residing on the first STS-1 of slot 1:
-
Deleting any VT 1.5 level circuit
-
Deleting a 1+1 protection group carrying VT 1.5 traffic in the Cerent 454
When in the Circuit Screen, deleting a VT circuit will affect Slot 1 of every node the circuit passes through that has traffic on slot 1, STS 1.
Deleting the 1+1 protection group will affect only the node where the protection group resides. This Field Notice applies to the following modules carrying traffic in slot 1:
-
DS1-14: all ports on slot 1
-
DS3-12: slot 1, port 1
-
DS3XM-6: slot 1, port 1
-
OC-3: slot 1, port 1, STS 1
-
OC-12: slot 1, port 1, STS 1
-
EC1-12: slot 1, port 1
-
E100T-12: Ethernet entire slot
Workaround/Solution
The workaround is to perform software resets on the active and standby XCVT cards for each node that the VT circuit passed through and that has traffic on slot 1.
-
Log into the Cerent 454 via the Cerent Management System (CMS).
-
Determine which XCVT is standby.
-
In the shelf view of CMS, right click over the standby XCVT and choose Reset from the menu.
-
Allow the XCVT to completely reboot.
-
Determine which XCVT is active.
-
In the shelf view of CMS, right click over the active XCVT and choose Reset from the menu.
Caution: This will cause a switch of XCVTs.In Cerent Systems you should have redundant Timing Communications and Control (TCC), XC, or XCVT cards so that when you switch you will switch to a standby card and the formerly active card will become standby and be reset.
-
Allow the XCVT to boot completely (that is, wait until the code is active).
Alternately, the problem can be avoided by not provisioning circuits on slot 1, STS1.
For More Information
If you require further assistance, or if you have any further questions regarding this field notice, please contact the Cisco Systems Technical Assistance Center (TAC) by one of the following methods:
Receive Email Notification For New Field Notices
Product Alert Tool - Set up a profile to receive email updates about reliability, safety, network security, and end-of-sale issues for the Cisco products you specify.