Q: Can I ignore OGG-01184 and force Replicat to continue? A: No. The process will abend every time. You must correct the file or move to the next sequence.
Q: Does this error cause data loss? A: Potentially, yes. Any changes after the truncated point in the affected trail file might be lost. A reload or reconciliation is recommended.
Q: Can I recover the missing 4 bytes if I have the exact record length? A: Only via advanced hex editing. Most users are better off rolling over and reloading.
Q: How do I avoid this when using OGG for replication across continents? A: Use GoldenGate’s built-in compression and encryption. Always transfer trails with guaranteed delivery (e.g., using OGG’s TCP/IP remote trail option with acknowledgment).
This article was last updated for Oracle GoldenGate versions 12.3 and 19c. Always refer to your specific OGG release documentation for version-specific behavior.
Trail Termination
The console spat the error for the third time:
ogg-01184 expected 4 bytes but got 0 bytes in trail
Maya stared at the hex dump. The stream was pristine — checksums matched, no corruption markers. But at the very end, where four bytes of trailing metadata should have been, there was nothing. Not zeros. Not nulls. Absence.
She scrolled up. The OGG file had played fine for eleven minutes and forty-three seconds. Then silence. Then the error.
"Four bytes," she whispered. "What's four bytes?"
Her colleague didn't look up. "CRC. Length. Sync flag. Depends on the codec."
"No," Maya said. "It's not missing. It was never written."
She ran a differential against the source recording — the one from the deep-sea hydrophone array, pulled up last week. The original had the four bytes: 0x4B 0x4E 0x4F 0x57. ASCII: KNOW. ogg-01184 expected 4 bytes but got 0 bytes in trail
The copy on her drive had a trail of zero bytes.
"Something ate the knowledge," she said.
The hydrophone had been listening to a trench no one had mapped. And something down there, she realized with a cold wash of certainty, did not want to be known. It had reached up through the file system — not corrupting, not deleting, just un-writing the last four bytes of every copy.
Like erasing a signature.
She looked at the error again: expected 4 bytes but got 0 bytes in trail.
Not a bug. A warning.
The trail was empty because the trail had been wiped. And whatever wiped it was still listening.
The Oracle GoldenGate error OGG-01184 occurs when a process (typically a Data Pump or Replicat) attempts to read a record from a trail file but encounters an unexpected end-of-file or a corrupted record trailer. Technical Review
The Cause: This error signifies that the process expected a 4-byte record trailer token but found 0 bytes instead. This usually indicates that the trail file was truncated or not fully written—often due to a disk space issue, a network interruption during file transfer, or a source process (Extract) crashing while writing.
The Checkpoint Conflict: You may also see a related error, OGG-01705, which occurs when the process's checkpoint position is actually beyond the physical size of the trail file. Recommended Action Plan
Validate Trail Integrity: Use the Logdump utility to inspect the specific Relative Byte Address (RBA) mentioned in the error. This helps determine if the file is truly empty at that point or just corrupted. Repump or Re-extract:
If the issue is in a remote trail (target side), try deleting the corrupted trail file and restarting the Pump process on the source to re-transmit the data.
If the local trail (source side) is corrupted, you may need to reposition the Extract process to a previous valid sequence number or RBA. Q: Can I ignore OGG-01184 and force Replicat to continue
Check System Resources: Verify that the destination disk is not full and that there are no "file handle shortages" on the host system.
Reference Official Support: For detailed recovery steps, Oracle documentation frequently points to Doc ID 1138409.1 on My Oracle Support, which provides specific instructions for handling trail file mismatches. Extract & Pump Abends — oracle-mosc
The error OGG-01184: Expected 4 bytes but got 0 bytes in trail is a critical Oracle GoldenGate message indicating that a process (usually a Pump or Replicat) failed to read a mandatory 4-byte record trailer token from a trail file. This typically occurs when a record is incomplete or the file has been truncated prematurely. Understanding the Root Causes
The "expected 4 bytes but got 0" condition signifies that the GoldenGate process reached a Relative Byte Address (RBA) where it expected to find metadata, but instead encountered the end of the file.
Trail File Corruption: This is the most common cause. A trail file may be corrupted due to underlying disk issues, filesystem failures, or an abrupt system shutdown that prevented the Extract from properly closing the file.
Abnormal Process Termination: If the source Extract process crashes while writing, it may leave a "short" record at the end of the trail file that lacks the necessary closing tokens.
Checkpoint Mismatch: Sometimes, the input checkpoint position for a Pump or Replicat is greater than the actual physical size of the trail file, leading the process to seek data that does not exist.
Network Issues: In remote trail scenarios, network interruptions during a transfer can result in a partial file being written to the target system. Step-by-Step Troubleshooting and Resolution 1. Identify the Corrupted Trail File and RBA
Check the GoldenGate Error Log (usually ggserr.log) to find the specific sequence number and RBA where the error occurred.
Example Error: ERROR OGG-01184 Expected 4 bytes, but got 0 bytes, in trail ./dirdat/no000007, seqno 7, reading record trailer token at RBA 246849346.. 2. Verify File Integrity
Compare the RBA mentioned in the error with the actual size of the trail file on the disk. If the RBA is larger than the file size, the file is definitely truncated. 3. Resolution Strategies
Option A: Automated Remote Trail Recovery (OGG 12.2+)If you are using Oracle GoldenGate 12.2 or higher, you can often recover remote trails automatically: Stop the Pump process on the source. Delete the corrupted trail file from the target.
Restart the Pump; it will automatically rebuild and re-send the missing trail files from the source. This article was last updated for Oracle GoldenGate
Option B: Repositioning the ProcessIf the corruption is at the very end of a trail file and the next trail file exists, you can skip the corrupted record:
Use ALTER REPLICAT to move past the error. Note that this may result in data loss for that specific record.
Option C: Re-extracting DataIf the local trail on the source is corrupted, you must re-position the Extract process to a point in the database logs (SCN or timestamp) prior to the corruption and regenerate the trails. Prevention Best Practices
Monitor Disk Space: Ensure the dirdat directory has enough space to prevent partial writes.
Use Proper Shutdowns: Always use the STOP command in GGSCI rather than killing OS processes.
Filesystem Stability: Host trail files on stable, high-performance filesystems to reduce the risk of I/O related corruption. OGG-01184 - Oracle GoldenGate Error Messages
Expected 3,number,0 bytes, but got 4,number,0 bytes, in trail 0, seqno 1,number,0, reading record trailer token at RBA {2, Oracle Help Center Extract & Pump Abends - Oracle Communities
Here’s a structured incident and troubleshooting report for the Oracle GoldenGate error:
Subject: Production Extract Abend Error Code: OGG-01184 Status: Critical
Error Code: OGG-01184
Message: Expected 4 bytes but got 0 bytes in trail
Category: Trail File Read Error / End-of-File Handling
If you are reading this, you have likely just encountered a nightmare scenario for any data replication engineer. Your Oracle GoldenGate (OGG) Replicat process has aborted with the cryptic message:
ERROR OGG-01184 Expected 4 bytes but got 0 bytes in trail file.
This error is not a simple configuration mismatch. It typically signals a serious structural problem in the trail file—the lifeblood of your GoldenGate replication. At its core, GoldenGate expected to read a 4-byte control field (usually a record length indicator or a checksum), but instead found an End-Of-File (EOF) marker or a null value (0 bytes).
When this happens, your target database stops synchronizing. Data latency begins to grow. And if not handled correctly, you risk data divergence between source and target.
This article provides a complete, step-by-step guide to diagnosing, fixing, and preventing the OGG-01184 error. We will cover everything from basic concepts to advanced surgical recovery techniques.
SLICwave Life Cycle possesses a wide range of data management solutions, called Base Tools, that can be acquired individually or in combination. These distinct, but sometimes overlapping, capabilities are designed to be as user-friendly as possible and allow users to deliver the specific functionality their projects require. Click on a Base Tool in the image above to jump to its description below!
