It is very interested a problem.
Check the cables from HDK to CMDU, and switches.
Maybe switches is not connected.
Switch on and off, and back to default seting.
It was a many problems of older options 71 and lower.

Hello folks, here is a print of nortel pbme502
maybe that is your problem, then talk to your vendor



Meridian 1 IODU/C Access Issue
This product bulletin is being issued as an advisory about a possible problem observed on a few sites where an IODU/C NT5D61AB/BB pack has not been accessible to the Meridian 1 system. The cards in question are:
        
NT5D61AB releases 4 and 6 – IODU/C (Input-Output Disk Unit with CD-ROM) cards
NT5D61BB releases 3, 4 and 5- IODU/C (Input-Output Disk Unit without CD-ROM) cards
Problem Description:
It has been observed on locations that one of each site’s IODU/C card stopped being accessible. During the midnight routines at these sites, the inaccessibility was noticed by the system, the card was disabled and the storage requirement defaulted to the other IODU/C card. On one site, this resulted in an initialization (INI) of the switch.

Though rare, it is felt that the potential for problems still remains and we would like to put out the appropriate information on how to recognize when the problem occurs and what can be done about it.

The problem occurs because of a timing issue between the M1 and the IDE to SCSI interface of the hard drive controller that is used in the IODU/C product. The interface and drive in question are used only in the aforementioned packs during idle times when the hard drive is not in use, the hard drive may stop functioning and will no longer be accessible to the switch. The next time that the switch attempts to access the drive, such as during a midnight routine, the inaccessibility will be discovered and the IODU/C card will be disabled.  Messages issued at this point will vary depending on the files that the system was trying to access, but they will commonly report that the drive was inaccessible.

Immediate symptoms may include TTY messages with one or both hard disks indicating “CMDU disabled not responding” and the failed IODU/C pack hard drive LED flashes four times repeatedly.

The impact of this is that the system will continue to run exclusively off of the non-disabled drive, until the drive in question is reseated or replaced.
Scope:
Although the problem occurs rarely, the potential for this problem is on all release 4 and 6 NT5D61AB and release 3,4&5 NT5D61BB cards. These releases were manufactured between April 1999 and December 2000.
Solution:
This problem has been resolved in release 7 of the NT5D61AB, which is now being shipped.
Field returns of release 4 and 6 boards have been modified with the new interface and upgraded to release 8 of the NT5D61AB card since December, 2000.
This problem has been resolved in release 6 of the NT5D61BB, which is now being shipped.
Field returns of release 4 and 6 boards have been modified with the new interface and upgraded to release 7 of the NT5D61BB card since December, 2000.
Recommended Actions:
1.    As an immediate workaround, the IODUC functionality can be recovered by reseating the pack.
2.    In the longer term, customers who are experiencing the condition noted above may receive replacement(s) free of charge effective with this notice.

reagrds
Fritz  

Thank you Fritz!

Hi,

Fritz is correct, I have also experienced that kind of problem before on system using that hardware and software rls. 23.37.

As an immediate solution, reseating of the card is effective, but as a solution to this problem, I have tried to re-install all, including the software, database cp rom iop rom and everything and it works. Until now I haven't experienced that same problem on that system since last year.

Lemonheads