The the following steps should be performed:
1. Cabling and GBIC:
a) was cabling checked?
b) was GBIC re-inserted?
c) was a different port on NPM and switch tested?
2. Crossbeam part:
1. Telnet to a particular NPM module and get the following:
a)GBIC info:
cat /proc/driver/cbsif/Geth<number>/sfp_info
b)NPM port info:
cat /proc/driver/cbsif/Geth<number>/port_info
cat /proc/driver/cbsif/Geth<number>/sw_mii_regs
Where <number> is a particular port number on the NPM card.
c) /var/log/messages either separately or as a part of "show-tech bundle"
3. Adjacent switch/router part:
a) get router/switch logs - any corresponding link flap or other related messages are present?
b) switch/router port side has a GBIC or is directly connected to the switch/router?
Workaround
No workaround available.