Issuing CA halts processing (JET_errLogDiskFull)

Hello Leo Walker,

The error JET_errLogDiskFull occurs when the transaction log directory for the CA’s Jet database runs out of disk space, which halts certificate processing. The good news is that this can be resolved safely with a combination of log truncation and disk expansion.

The first step is to free up space by performing a safe log truncation. Stop the Certificate Services, then back up the CA database using certutil -backupdb and certutil -backupkey. After the backup, you can run eseutil /mh against the database to confirm its state, and then use eseutil /r to replay and truncate logs. This ensures no pending transactions are lost. Once truncation is complete, restart Certificate Services.

In parallel, it’s strongly recommended to expand the volume hosting the log files or move the log directory to a larger disk. This prevents the issue from recurring under heavy issuance loads. You can configure the log path in the CA properties, but be sure to update permissions accordingly.

As a best practice, monitor disk usage regularly and set alerts for the log directory so you can act before it fills up. This combination of truncation, expansion, and monitoring will stabilize your CA and prevent future outages.

I hope the response provided some helpful insight. If you find this answer useful, please hit “accept answer” so I know it addressed your concern.

Jason