🍪

Essential cookies keep authentication working. With your permission, we also use analytics to improve the product. Privacy Policy

DDataEngPrep.tech
Home
PricingBlog
Sign InStart Free→
Home/Questions/System Design/Architecture/What are the best practices for logging and monitoring bad data?

What are the best practices for logging and monitoring bad data?

System Design/Architecturemedium0.3 min read

Reviewed by Aditya Kumar · Last reviewed 2026-03-24

(1) Structured logging—JSON with record_id, rule_id, severity, sample. (2) Centralized—ELK, Splunk, CloudWatch. (3) Metrics—failed count per rule; alert on spikes. (4) DLQ—store bad records for reprocessing. (5) Dashboards—DQ score, trends. (6) Sampling—log sample, not all. WHY:...

🤖 Analyze Your Answer
Frequency
Low
Asked at 1 company
Category
179
questions in System Design/Architecture
Difficulty Split
15E|6M|158H
in this category
Total Bank
1,863
across 7 categories
Part of the Data Engineering System Design Interview Preparation Hub
Explore Data Engineering System Design Hub→
Reported in Interview Loops AtClick to view company-specific questions
🏢 PWC Interview Hub→
Interview Pro Tip

Red Flag: Blocking pipeline on bad data. Pro-Move: 'DLQ + sampled logging; we replay from DLQ after fix; metrics feed into DQ dashboard; 99.9% good data path unaffected.'

Expert Answer
56 words

(1) Structured logging—JSON with record_id, rule_id, severity, sample. (2) Centralized—ELK, Splunk, CloudWatch. (3) Metrics—failed count per rule; alert on spikes. (4) DLQ—store bad records for reprocessing. (5) Dashboards—DQ score, trends. (6) Sampling—log sample, not all. WHY: Root cause without full rerun. SCALABILITY: Sampling and aggregation; avoid log explosion. COST: Log volume = cost; sample and aggregate.

⚡
Pro Tip

Red Flag: Blocking pipeline on bad data. Pro-Move: 'DLQ + sampled logging; we replay from DLQ after fix; metrics feed into DQ dashboard; 99.9% good data path unaffected.'

Related System Design/Architecture Questions

hardWhat architecture are you following in your current project, and why?FreeeasyCDC During Migration - explain approaches for real-time Change Data CaptureFreehardBriefly explain the architecture of Kafka.FreehardDescribe the data pipeline architecture you've worked with.FreehardExplain the trade-offs between batch and real-time data processing. Provide examples of when each is appropriate.Free

According to DataEngPrep.tech, this is one of the most frequently asked System Design/Architecture interview questions, reported at 1 company. DataEngPrep.tech maintains an editor-reviewed database of 1,863 data engineering interview questions across 7 categories.

← Back to all questionsMore System Design/Architecture questions →
Topic Hubs
All Topic Hubs (12 Competencies) →All 1,863+ QuestionsSQL Interview QuestionsApache Spark QuestionsPySpark QuestionsPython for Data EngineersSystem Design InterviewData Modeling & WarehousingStreaming (Kafka/Flink)SQL Window FunctionsETL Pipeline Design
Company Hubs
All Company Hubs (100+ Companies) →AmazonGoogleMetaDatabricksSnowflakeNetflixUberStripeMicrosoftAppleGoldman SachsAWS Engineering
Academies & Guides
All Guides & ArticlesData Engineering AcademyForward Deployed AI AcademyClient Simulation StudioApache Airflow QuestionsAzure Data EngineerBehavioral & STAR MethodCloud & Distributed Tools
AI Tools & Products
Answer Analyzer (Free)AI Mock InterviewsSQL PlaygroundATS Resume AnalyzerOffline PDF Answer VaultsMembership & Pricing
Company
About & Editorial PolicyContact UsAI DisclosureDisclaimerTerms of ServicePrivacy Policy
© 2026 DataEngPrep.tech. All rights reserved.
AboutBlogContactDisclaimer