| Circular logging is a Exchange Server feature that | | | | Exchange deletes the log files immediately after |
| implements recycling of logs. Microsoft Exchange | | | | writing the data to the database, for which the |
| Server writes the data to be committed to the | | | | information is traced out by Edb.chk file. Now, if a |
| database in transaction logs before actually writing | | | | process blocks the Edb.chk file for a considerable |
| it. If circular logging is enabled and four logs have | | | | period of time and prevents Exchange to update |
| been filled, it assumes that the first log as | | | | it, the file may get deleted before it could be |
| committed and thus, recycles the logs in order to | | | | updated. Thus, the checkpoint gets lost if the |
| save disk space. But it comes with a major flaw | | | | database suffers an unexpected stop. When you |
| that prevents disaster recovery. If the database | | | | restart the server, the Edb.chk file points to a log |
| is corrupted while the feature is enabled, | | | | file that doesn't exit anymore and hence, the |
| Exchange can only restore as far as the last | | | | database doesn't start. |
| backup is available. In case a suitable backup is | | | | Solution |
| unavailable, you are suggested to opt for | | | | If the exact cause is known and the errors are |
| Exchange Repair solutions that are powerful and | | | | occurring only because of Edb.chk file, delete it |
| safe too at repairing a corrupted Exchange | | | | and database service. But if the cause is different, |
| database. | | | | the database might get damaged. |
| For example, you observe an unexpected | | | | To achieve recovery, you should not use eseutil |
| shutdown with an Exchange database. After this, | | | | r command without /is or /ds switches. This is |
| when you try to start it, an 'JET_errFileNotFound' | | | | because at this point, a new Edb.log file can get |
| error is displayed with a numerical value, such as | | | | created and Exchange may try to repair using |
| 4294965485, -1811 or 0xfffff8ed. When you | | | | incorrect set of log files. Though you can delete |
| view the application event log, it shows events | | | | the Edb.chk file, but the database remains |
| 1120 and 5000. | | | | corrupted. |
| Cause | | | | For getting successful results from a corrupted |
| Events 1120 and 5000 generally show database | | | | Exchange database, it is suggested to use |
| inconsistency that prevent the database to start. | | | | Exchange Repair products in case if no good |
| You should see their description for the exact | | | | backup is there. Exchange Repair tools are |
| reason. | | | | high-end and safe database repair utilities that can |
| One probable cause could be that circular logging is | | | | repair and restore a corrupted Exchange |
| enabled and error lies in checkpoint file, usually | | | | database. |
| Edb.chk file. Since the circular logging is enabled, | | | | |