indicates that an Oracle GoldenGate process (typically a ) expected to read 4 bytes for a record trailer but found 0 bytes instead. This usually signifies trail file corruption
or a situation where the reader's checkpoint position is beyond the actual physical end of the file Oracle Communities Immediate Troubleshooting Steps Identify the Point of Failure : Check the report file ( VIEW REPORT
) to find the exact trail file sequence number and Relative Byte Address (RBA) where the error occurred. Verify File Size
: Log into the OS and compare the physical size of the trail file with the RBA reported in the error. If the RBA is larger than the file size, the process is attempting to read non-existent data. Check for Concurrent Writes
: Ensure no other process (e.g., a secondary Extract) is accidentally writing to the same trail file, which can overwrite data and cause corruption. Oracle Communities Resolution Guide Option 1: Repositioning (Most Common Fix)
If the trail file is missing the record trailer (truncated), you may need to skip the corrupted record or reposition the process to the next valid position. Skip to the next RBA ALTER
: If the RBA is unknown, move the process back slightly to a known good time and let it re-process (it will skip duplicates automatically if configured correctly). ALTER
feature to rebuild the corrupt target trail from the source. Oracle Help Center Stop the process.
Delete the corrupted trail file and any subsequent files in that sequence on the target. Restart the Extract Pump
; it should automatically fetch the missing data from the source trail files. Oracle Help Center Option 3: Manual Trail Regeneration (ETROLLOVER)
If the source trail itself is corrupted, you must force the source Extract to start a new file. www.oracle-scn.com ALTER EXTRACT
This creates a new trail file (e.g., increments sequence from Reposition the Pump to the start of this new sequence: ALTER PUMP
: Interrupted transfers between source and target can lead to incomplete files. Improper Shutdowns
: Killing OGG processes or OS-level crashes while writing to trails. Disk Space Issues
: Running out of space on the target mount point, preventing the complete writing of record trailers. www.oracle-scn.com GGSCI commands
to verify the current checkpoint RBA versus the actual file size? Extract & Pump Abends — oracle-mosc
The error message OGG-01184: Expected 4 bytes but got 0 bytes in trail is the Oracle GoldenGate equivalent of a "sudden death" notification. It is a low-level I/O error that indicates the Extract process reached the end of a trail file expecting to find a complete record header (4 bytes) but found nothing but empty air.
Here is a deep technical narrative regarding this error, structured as a forensic investigation.
If the Extract process was terminated abruptly (e.g., a server crash or a kill -9 command) while writing to the current trail file, the file may be "truncated." The file exists and has a size greater than 0, but the data stream cuts off in the middle of a record. When the Replicat reaches this cut-off point, it expects the next chunk of data but hits the EOF.
stop extract ext1 alter extract ext1, extseqno 000003, extrba 0 start extract ext1
indicates that an Oracle GoldenGate process (typically a ) expected to read 4 bytes for a record trailer but found 0 bytes instead. This usually signifies trail file corruption
or a situation where the reader's checkpoint position is beyond the actual physical end of the file Oracle Communities Immediate Troubleshooting Steps Identify the Point of Failure : Check the report file ( VIEW REPORT
) to find the exact trail file sequence number and Relative Byte Address (RBA) where the error occurred. Verify File Size
: Log into the OS and compare the physical size of the trail file with the RBA reported in the error. If the RBA is larger than the file size, the process is attempting to read non-existent data. Check for Concurrent Writes
: Ensure no other process (e.g., a secondary Extract) is accidentally writing to the same trail file, which can overwrite data and cause corruption. Oracle Communities Resolution Guide Option 1: Repositioning (Most Common Fix)
If the trail file is missing the record trailer (truncated), you may need to skip the corrupted record or reposition the process to the next valid position. Skip to the next RBA ALTER
: If the RBA is unknown, move the process back slightly to a known good time and let it re-process (it will skip duplicates automatically if configured correctly). ALTER
feature to rebuild the corrupt target trail from the source. Oracle Help Center Stop the process.
Delete the corrupted trail file and any subsequent files in that sequence on the target. Restart the Extract Pump
; it should automatically fetch the missing data from the source trail files. Oracle Help Center Option 3: Manual Trail Regeneration (ETROLLOVER)
If the source trail itself is corrupted, you must force the source Extract to start a new file. www.oracle-scn.com ALTER EXTRACT
This creates a new trail file (e.g., increments sequence from Reposition the Pump to the start of this new sequence: ALTER PUMP
: Interrupted transfers between source and target can lead to incomplete files. Improper Shutdowns
: Killing OGG processes or OS-level crashes while writing to trails. Disk Space Issues
: Running out of space on the target mount point, preventing the complete writing of record trailers. www.oracle-scn.com GGSCI commands
to verify the current checkpoint RBA versus the actual file size? Extract & Pump Abends — oracle-mosc extrba 0 start extract ext1
The error message OGG-01184: Expected 4 bytes but got 0 bytes in trail is the Oracle GoldenGate equivalent of a "sudden death" notification. It is a low-level I/O error that indicates the Extract process reached the end of a trail file expecting to find a complete record header (4 bytes) but found nothing but empty air.
Here is a deep technical narrative regarding this error, structured as a forensic investigation.
If the Extract process was terminated abruptly (e.g., a server crash or a kill -9 command) while writing to the current trail file, the file may be "truncated." The file exists and has a size greater than 0, but the data stream cuts off in the middle of a record. When the Replicat reaches this cut-off point, it expects the next chunk of data but hits the EOF.
stop extract ext1 alter extract ext1, extseqno 000003, extrba 0 start extract ext1