db backup error

Hi,

Following is my transaction backup command.

"BACKUP LOG prod_cust TO pc_0930_tran WITH INIT"

Usually get this kind of message in the task log file:

"BACKUP LOG prod_cust TO pc_0930_tran WITH INIT"
Processed 173 pages for database 'prod_cust', file 'pcprod_log' on file 1.
BACKUP LOG successfully processed 173 pages in 1.438 seconds

While I got the following message this morning.

"BACKUP LOG prod_cust TO pc_0930_tran WITH INIT"
There is no current database backup. This log backup cannot be used to roll
forward a preceding database backup.
Processed 93 pages for database 'prod_cust', file 'pcprod_log' on file 1.
BACKUP LOG successfully processed 93 pages in 1.367 seconds (0.553 MB/sec).

Does anyone know what the second message mean?

Did you truncate the log before this backup and did not start a full backup?

Or you could have changed the database recovery model to Simple then backup t full and this is the first backup after that.

To roll forward using a transaction log backup you need a full backup as the starting point.

Or somehow your msdb database lost backup history records. Query backupset table to see if you have any full backup.

In this case, you should do db full backup first then backup logs.