Error message: %TCP-2-INVALIDTCB ==> what does it mean ?

[abekeris]

Jul 29 17:28:28: %TCP-2-INVALIDTCB: Invalid TCB pointer: 0x47244F40

-Process= "Virtual Exec", ipl= 0, pid= 103

-Traceback= 40700C8C 407053D8 40708540 404D6468 4050A4E4 405B9714 405B9700

Jul 29 17:28:43: %ALIGN-3-CORRECT: Alignment correction made at 0x4070590C reading 0xD0D0E01

Jul 29 17:28:43: %ALIGN-3-TRACE: -Traceback= 4070590C 40702094 404D7B20 404D4B0C 404D63CC 4050A4E4 405B9714 405B9700

Jul 29 17:28:43: %ALIGN-3-CORRECT: Alignment correction made at 0x40705910 reading 0xD0D0DE9

Jul 29 17:28:43: %ALIGN-3-TRACE: -Traceback= 40705910 40702094 404D7B20 404D4B0C 404D63CC 4050A4E4 405B9714 405B9700

[a.awan]

I think you are experiencing a software issue, possibly a bug. Is this a recurring problem? The Cisco Error decoder shows:

. %ALIGN-3-CORRECT: Alignment correction made at [hex] [chars]ing [hex]

An alignment error has been detected and corrected. Alignment errors are due to misaligned reads and writes caused by a software failure. Correcting alignment errors consumes processor resources and may result in a performance p enalty. If there are recurring alignment errors, CPU utilization may be seriously affected.

Recommended Action: To take advantage of recent fixes, upgrade your system to the latest Cisco IOS software release in your release train. If this message recurs, enter the show log, show alignment and show tech-support commands, contact your Cisco technical support representative, and provide the representative with the gathered information.

[abekeris]

we are at the last IOS version (12.2.20S4) for a Cisco 7304.

It occurs several times a day and when we try to telnet the router, it times out or we have to wait a lot of time in order to get the prompt.

Have any idea of what is happening ?

[a.awan]

I strongly suspect that this is a bug you are running into. I will recommend opening a TAC case and having them look into this error. There are a lot of TCP related bugs associated with this particular software release you are running and i will not be surprised if this is a new one.

[yaqoobkk]

I got the same message .. %TCP-2-INVALIDTCB: Invalid TCB pointer: 0x44886C8 -Process= "HTTP CORE", ipl= 0, pid= 219...(C2960S-UNIVERSALK9-M), Version 12.2(53)SE2 and by blocking the switch IP from internet no more messages obervsered.

Thanks

[Joseph W. Doherty]

No doubt blocking traffic that triggers a bug (generally what I understand most tracebacks are - even 19 years later) is effective, especially as a short term fix, but I would consider trying to obtain a more permanent fix.

I haven't looked, but I suspect there has been some software revisions since your posted IOS version.

[yaqoobkk]

My complete message %TCP-2-INVALIDTCB: Invalid TCB pointer: 0x44886C8 -Process= "HTTP CORE", after checking found that http and secure-http both were enabled and i have disabled both and no more messages .....HTTP CORE

Thanks

[Joseph W. Doherty]

If there's a "bug" (software defect) in the HTTP/HTTPS code, disabling HTTP, likely would avoid the errors messages, as you've noted.  However, without knowing the true root cause of the "bug", side effects (other issues) might still arise.

I would recommend still considering moving to a later IOS patch version, but again, what you've done might be "good enough".

Thank you for posting the update!