An opinionated roadmap to become an SRE (Concepts > Tools)

• Concepts
  • Fallacies of distributed computing
  • Synchronous vs. asynchronous
  • Event log vs. message queue
  • Exactly-once delivery
  • Different types of message failure
  • Orchestration vs. choreography
  • Causality
  • CDN
  • Hashing
    • Consistent hashing
    • Geohashing
    • Perfect hashing
  • Read-heavy vs. write-heavy impacts
  • Federation
  • Latency
    • Latency, throughput, goodput
    • Latency numbers every programmer should know
    • How to prevent latency variability
    • Tail latency
  • How to reduce sharing
  • Idempotency
  • Load balancer
    • Concepts
    • Layer 4 vs. layer 7 load balancer
  • Liveness vs. safety properties
  • Microservices: pros and cons
  • REST
  • gRPC
  • Service mesh
  • Source of truth
  • Stateful vs. stateless
  • Total vs. partial order
  • Why can't we rely on the system clock in distributed systems
  • Vector clock
• Cache
  • When to use a cache
  • Cache-aside vs. read-through
  • Eviction policy
  • Refresh-ahead
  • Write-through vs. write-back
  • Distributed cache
  • Performance cache vs. capacity cache
• Databases
  • Different types of databases
    • NoSQL vs. SQL databases
    • Relational vs. document
    • Column-oriented databases
    • Graph databases
    • Vector database
    • Objects-based storage
  • ACID
  • Partitioning
    • Criteria
    • Methods
    • Replication vs. partition
  • Hotspot
  • CALM theorem
  • CAP theorem
  • PACELC theorem
  • Cardinality
  • Chain replication
  • Consensus
  • Concurrency control
  • Consistency models
  • Isolation levels
  • Serializability
  • Linearizability
  • CRDT
  • Indexes
    • Tradeoff
    • Primary vs. secondary indexes
  • Denormalization
  • View & materialized view
  • Transaction
  • Distributed transactions downsides
  • Strategies to handle rebalancing
  • Leader election
  • MVCC
  • N+1 select problem
  • Quorum
  • Raft
  • Read repair
  • Single-leader, multi-leader, leaderless replication
  • Split-brain
  • 2PC
  • 3PC
  • WAL
  • Write and read amplification
• Data structure
  • Probabilistic data structures
    • Bloom filter
    • Count-min sketch
    • HyperLogLog
  • Storage
    • LSM tree
    • B-tree
    • SSTable

• Concepts
  • Difference between availability, resiliency, robustness, fault-tolerance, and reliability
  • Why is it wrong to target 100% availability
  • Blast radius
  • Failure domain
  • Cascading failures
  • Hard vs. soft dependencies
  • Scalability
    • Concepts
    • Knee point
    • Ceiling
  • Number one source of outages
  • Tail tolerance
  • Toil
• Patterns/Anti-patterns
  • Bulkhead pattern
  • Circuit breaker
  • Exponential backoff
  • Jitter
  • Graceful degradation
  • Load shedding
  • Retry amplification
  • Backpressure
  • Rate limiting
  • Request hedging
• Practices
  • Chaos engineering

• Concepts
  • What's the difference between monitoring and observability
  • Trace vs. metric vs. log
  • Golden signals
  • Observer effect
  • Percentile
  • Streetlight anti-method
  • Time-series based monitoring lies
  • USE method
  • Main metrics for cache
  • Why should we be careful about average performance metrics
• Alerting
  • Alerting strategy
  • Alerting fatigue concept
  • Characteristic of a good alert
  • Slow vs. fast burn alert

• Concepts
  • Bake time
  • Feature flag
  • Feature freeze
  • Rollout supervision
• Rollout types
  • Blue green rollout
  • Canary rollout
  • Progressive rollout
  • Shadow rollout

• Concepts
  • SLI vs. SLO vs. SLA
  • Error budget
• SLO
  • Difference between KPIs and SLOs
  • Benefits of having alerts based on SLOs
  • Why is exceeding an SLO not necessarily a good thing
  • SLO for data (freshness, completeness, consistency, etc.)
  • SLO for mobiles
  • SLO for services

• Container
• Container orchestration

• Scripting
• Filesystem
• Memory
• Processes
• Resource utilization
• Network

• ARP protocol
• Bandwidth
• BGP
• CoDel
• CORS
• DNS
• Ping vs. heartbeat
• TCP
  • TCP vs. UDP
  • Congestion control
  • Connection backlog
  • Flow control
  • Handshake
• HTTP
• HTTP/2
• Head of line blocking
• Health checks: passive vs. active
• Internet model
• NTP
• OSI model
• Routers
• Switch
• Network topologies
• What happens if you type google.com in your browser

• Authentication
• Certificate
• Certificate authority
• Cipher
• Confidentiality
• Encryption
• TLS
• PKI
• Signature

• Core analysis loop
• Correlation vs. causation
• First principle
• Five whys technique
• Incident management
  • How to address an incident (assess, mitigate, resolve)
  • Incident roles
  • How to write a postmortem
  • 3C principles (Coordinate, Communicate, maintain Control)

• SRE role
• Version control

• Communication
  • Writing
  • Oral
  • Presentation
  • The XY problem
• Collaboration
• Problem solving
• Curiosity
• Navigating ambiguity
• Staying humble