Cisco WS-X4K-MUX enterprise networking (routers/Catalyst switches) Switch / Carrier Ethernet Line Card

The Cisco WS-X4K-MUX is a redundant supervisor MUX (multiplexer) module for the Cisco Catalyst 4507R and 4510R chassis, the interconnect card that allows these switches to run dual supervisor engines with automatic failover between them. It sits in a dedicated slot separate from the supervisor engines themselves and handles the switchover signalling between the active and standby supervisor, which is what makes redundant supervisor operation possible on the 4507R/4510R platform. A faulty MUX module can prevent supervisor failover from working correctly even if both supervisors themselves are healthy, so it is worth testing as part of diagnosing a failed failover event rather than assuming the supervisors are always at fault. Tech-Star is UK-based and ships worldwide.