Confd_load for restoring the configuration is not working

CDB and CDB API
1

We are testing the downgrade of confd from version 7.2.1 to 6.3. When the downgrade is triggered, the following error is encountered:

5-May-2025::09:51:42.115 orchestrator confd[2199813]: confd embedded apps in phase0: []
5-May-2025::09:51:42.169 orchestrator confd[2199813]: - CDB boot error: Old and unsupported C.cdb file format
To recover do "rm -f /data/cdb/.cdb"*

As recommended, we removed the .cdb files, and the downgrade was completed successfully. However, when we attempted to restore the confd data from the backup file, we encountered some errors.

root@orchestrator:/# /var/confd/bin/confd_load -i -F xml -l backup.xml -d -d -m
TRACE Connected (maapi) to ConfD
attaching to init session…
TRACE MAAPI_ATTACH DEBUG item does not exist - User sess -2 doesn’t exist

  • → CONFD_ERR*
    confd_load: 292: maapi_attach_init(sock, &tid) failed: item does not exist (1): User sess -2 doesn’t exist

Please help me on this confd_load part.

Thanks
Vinuta MB

2

I moved the backup file /data/cdb folder, now it is giving different error

root@orchestrator:/# /var/confd/bin/confd_load -m -l /data/cdb/backup.xml -d -d -m
TRACE Connected (maapi) to ConfD
starting user session ctxt=system user=system groups=[system]
TRACE MAAPI_START_USER_SESSION → CONFD_OK
TRACE MAAPI_START_TRANS DEBUG item is not writable - Data store is not writable

  • → CONFD_ERR*
    TRACE MAAPI_START_TRANS → CONFD_OK
    TRACE MAAPI_LOAD_CONFIG_FILE DEBUG external error - Error on line 4: object is not writable: /nacm:nacm/nacm:denied-notifications

  • → CONFD_ERR*
    confd_load: 662: maapi_load_config(sock, tid, flags, abspath(argv[0])) failed: external error (19): Error on line 4: object is not writable: /nacm:nacm/nacm:denied-notifications

developer log level is set to trace, but it not showing any errors

3

Hi,

Downgrades are often tricky and a downgrade from one very old release to an even older release would be even more so.

The trouble you will run into when trying to reload a newer configuration into an older one is if some structure has changed. You are getting a hint of that with the error about nacm:denied-notifications. I did not look into the history of that area of the YANG, but you might do that and see if your are trying to add some data (from your backup.xml) that doesn’t have a model, or if that model has changed.

I suggest that you try to reload the newer configuration into the older configuration in small pieces to see what is compatible and what is not. If this is a one-off effort, then you may be done. If you are trying to do this across a number of devices, it might help you know how to automate.

Best,
Scott