IE-2000-8TC-G-E blocked port

[CO1]

Dear all,

I have an issue that is driving me mad. I have several IE-2000-8TC-G-E built into a machine. They are connected to some custom designed circuit boards as well as servo controllers and a number of MOXA devices. One FE port is connected to a Kontron SBC running VxWorks with a board support package supplied by Kontron. This one particular port is consistently blocked by STP when VxWorks is running. It is not blocked when the board is in its Bios or bootloader. I have captured the communication between the devices and STP packets flow from the switch but not from the SBC. Disabling STP solves the problem.

Every thing is brand new. I have tried with several switches, cables and SBCs. It's all the same. What is going on here? What's blocking the port?

Best regards

Christian

[marce1000]

- Do you have any more info from show logging when this happens (from the IE) , and or configure syslogging to  a syslog server on it, and examine syslog messages from the IE around the time the port gets blocked.

M.

[CO1]

Here is what I managed to find.

From show platform debug errors I get:

Interface :Fa1/6

Error Code: ALERT-5-STP_BLOCK
Timestamp: 2006 01 02 00 01 52
Description: This port is blocked by Spanning Tree Protocol (STP).
Recommendation: Make sure that no Spanning Tree Protocol loops exist in the network.

From show logging I get tons and tons of:

*Jan 2 00:05:18.112: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet1/6, changed state to up
*Jan 2 00:05:26.182: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet1/6, changed state to down
*Jan 2 00:05:28.187: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet1/6, changed state to up
*Jan 2 00:05:36.232: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet1/6, changed state to down
*Jan 2 00:05:38.245: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet1/6, changed state to up

Again, there is only a Kontron SBC with one ethernet interface on the port. No loops. What happens if the ports disagree on autonegotiation? I have this nagging suspicion that VxWorks reinitializes the network hardware when it boots and that it somehow configures it differently from the bootloader.

Best Regards

Christian

[balaji.bandi]

what is the configuration of  Interface FastEthernet1/6 ?

[CO1]

Well, I have only run the Express Setup; ie., admin ip, passwords. Other piece of information, the situation is the same regardless of port. I suspect something that is software configurable either in the switch or in VxWorks and ends up in an incompatible config. We have used dumb switches for years without any problems. I only need a few of the IE-2000's advanced features. I have another Kontron SBC model running with VxWorks without problems. It's only this particular model / VxWorks combo that causes trouble.



I can get it to work occasionally if I do a combination of unplugging the board during boot, reconnect it several times etc. I have not found a system that can get it to work reliably.



I keep returning to the idea that this is somehow a software / configuration thing, but why is STP involved when only the switch use it? And why does all the other devices work then? The only thing I can think of is autonegotiation of speed, duplex, mdi-x vs fixed configs, but how can that affect STP?



Best regards,

Christian