Title
HitAnomaly: Hierarchical Transformers for Anomaly Detection in System Log
Abstract
Enterprise systems often produce a large volume of logs to record runtime status and events. Anomaly detection from system logs is crucial for service management and system maintenance. Most existing log-based anomaly detection methods use log event indexes parsed from log data to detect anomalies. Those methods cannot handle unseen log templates and lead to inaccurate anomaly detection. Some recent studies focused on the semantics of log templates but ignored the information of parameter values. Therefore, their approaches failed to address the abnormal logs caused by parameter values. In this article, we propose HitAnomaly, a log-based anomaly detection model utilizing a hierarchical transformer structure to model both log template sequences and parameter values. We designed a log sequence encoder and a parameter value encoder to obtain their representations correspondingly. We then use an attention mechanism as our final classification model. In this way, HitAnomaly is able to capture the semantic information in both log template sequence and parameter values and handle various types of anomalies. We evaluated our proposed method on three log datasets. Our experimental results demonstrate that HitAnomaly has outperformed other existing log-based anomaly detection methods. We also assess the robustness of our proposed model on unstable log data.
Year
DOI
Venue
2020
10.1109/TNSM.2020.3034647
IEEE Transactions on Network and Service Management
Keywords
DocType
Volume
Log data analysis,anomaly detection,hierarchical transformers
Journal
17
Issue
ISSN
Citations 
4
1932-4537
6
PageRank 
References 
Authors
0.43
0
7
Name
Order
Citations
PageRank
Shaohan Huang15710.29
Yi Liu2186.19
Carol Fung3403.34
Rong He461.10
Yining Zhao561.10
Hailong Yang63311.51
Zhongzhi Luan714044.73