Transfer Log-based Anomaly Detection with Pseudo Labels

Log-based anomaly detection is an important task for service management and system maintenance. Although anomaly labels are valuable to learn anomaly detection model, they are difficult to collect due to their rarity. To tackle this problem, existing methods employ domain adaptation algorithms to transfer anomaly detectors from labeled source domain to unlabeled target domain. However, most of those methods focus on key performance indicator anomaly detection. The semantic information in logs plays an important role in log-based anomaly detection. Therefore, adaptation methods need to consider how to transfer the semantic information in logs. In this paper, we propose a simple and effective adaptation method to transfer log-based anomaly detection model with pseudo labels. In our work, we first train a detection model with labeled samples as a pseudo-label annotator. Then we use it to assign pseudo-labels to unlabeled samples and train anomaly detectors as if they are true labels. Both models share the same feature extraction part, which can help model to transfer the semantic information in logs. We evaluated our proposed method on three log datasets. Our experimental results demonstrate that our method has outperformed other baseline methods.