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Link status down on 4250XL sensors

Good Morning,I have 6 4250XL IDS sensors. I am using VMS1.2 to manage them. I have them all upgraded and added to the IDS MC. I have int3 and int4 added to Group 0. The interfaces are in a up state but the link status is down on all sensors. I have monitor sessions configured with trunking to a number of VLANS using the fiber ports on the sensors. Any ideas what I need to do in order to get the link status up and start seeing statistics and events. Thanks for any replies.

Cisco Employee

Re: Link status down on 4250XL sensors

Also verify that you have done a "no shutdown" on each of the interfaces.

Other things to try:

1) Remove the span configuration on the switch just to see if the sensor will link up to a normal switch port.

2) Verify that the switch ports have been configured for auto speed and link. The 4.1 sensors only support auto speed and link. If you want to hardcode the speed to 1000Mbps, then you would need to upgrade to version 5.0 on the sensor.

3) If using an SC style connector on the switch, then verify that you have the TX and RX cables plugged into the correct TX and RX connector on the switch. It can be easy to swap those accidentally.


Re: Link status down on 4250XL sensors

The fiber interface on the 4255XL are not the most stable. They frequently go down when changing anything, even as minor as a signature tuning. Watch them closely and reboot as many times as necessary. There will be a maintenance release to 4.1.5 comming out next week (or two) to address this.

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