Roadmap

Difficulty

• A: Basic, concept (a 1st year CS student can learn)
• B: Intermediate (a fresh CS graduate can learn)
• C: Advanced topic
• D: Expert

Courses

• https://www.karanpratapsingh.com/courses/system-design

Concepts

Golang

• Syntax
  • https://go.dev/tour/welcome/1
  • https://www.youtube.com/playlist?list=PL64wiCrrxh4Jisi7OcCJIUpguV_f5jGnZ
• 🧵 Concurrency (B)
  • Goroutines (B)
  • Mutex (B)
  • Channels (B)
  • Context (B)
• HTTP
  • Client (net/http) (B)
    • Request
      • Setting/Getting Header
      • Setting/Getting Query Parameters
      • Custom Client
        • Custom Timeout
        • HTTP-trace
        • Custom transport
          • Skip TLS verify
      • Dump response
  • Server
    • net/http
    • gorilla/mux
    • labstack/echo
      • Advanced request multiplexing
      • Group register
      • Middlewares
        • JWT
        • Prometheus
• JSON marshal/unmarshal
• Config Management (spf13/viper/koanf/spf13/pflag)
  • Environment Variables
  • YAML/JSON/TOML
• CLI (cobra)
  • sub-commands
  • flags
• gRPC (d)
  • Protobuf
  • Code generation (which should be communicated well)
  • interceptors
    • Prometheus
    • log
• Databases
  • gorm
  • atlas
  • redis/go-redis
  • redis/rueidis
  • client mysql
  • client mongo
  • client etcd
• Testing
  • Unit testing
  • testify
  • BDD
    • gingko
    • gomega
• Jaeger tracing (d)
• Prometheus Exporter SDK

Network

• 📖 Network Warrior (first 12 chapters)
• 📖 Networking for Systems Administrators (IT Mastery)
• 🔗 The complete flow of entering a URL in your browser
• OSI layers (a)
  • L1:
    • hub
  • L2:
    • MAC (a)
    • vLAN (b)
      • Computer networking introduction: heavily visualized → such a brain friendly way of learning the fundamentals of network.
    • vrrp (b)
    • ARP (a)
  • L3
    • sub-netting, gw (a)
    • ip classes (A,B,C) private/public (a)
    • localhost (a)
    • link local (b)
    • Routing protocol (a)
      • routing table (a)
      • OSPF (b)
      • BGP (c)
        • iBGP, eBGP (c)
        • BGP params (d)
        • BGP loop prevention mechanism (d)
        • BGP communities (d)
  • L4
    • TCP handshake (a)
    • NAT (a)
    • TCP flow (b)
    • VxLAN
      • Computer networking introduction: heavily visualized → such a brain friendly way of learning the fundamentals of network.
    • L5
    • TLS handshake
      • asymmetric crypto (a) somehow
      • digital signature (a)
      • CA and verification (a)
      • SNI (c)
      • ALPN (c)
    • L6
    • L7
    • HTTP (a)
      • Methods (GET/POST/…)
      • Headers
      • URI, Path and Query parameter
      • CORS (c)
    • HTTP2 (b)
    • gRPC (c)
    • DNS (a)
      • recursive resolution
      • records: A,AAAA, CNAME
• Network bonding
  • 0, 1 (b)
  • 4 lacp 802.3ad (c)
• Packet NIC flow (d)
  • dram
  • ring buffer
  • driver
  • XDP
• MPLS (d)
• FRR (d)
• VRF (d)

Linux

• TODO: add LPIC topic + LinuxFun
• systemd (a)
• iptables https://iximiuz.com/en/posts/laymans-iptables-101/
• eBPF (d)
• Netfilter
  • vrf (d)
  • route tables, pbr (c)
  • route (b)
  • netns (b)
  • veth pair (b)
  • bridge (b)
  • vlan aware bridge (c)
  • 802.1q (c)
• namespaces
  • nsenter
  • lsns
  • types:
    • mnt
    • pid
    • net
    • ipc
    • uts
    • user
    • cgroup
    • time
• cgroups (c)
  • cgroupv1 vs cgroupv2 (d)
• kexec (d)
• io_urun (d)
• storage
  • lvm
    • pv
    • vg
• file
  • ACL
  • UID, GID
  • SELinux ls -Z
• Docker
  • Great resource for introduction to the container underlying concepts→ Cgroups, namespaces, and beyond: what are containers made from?
  • How containers work by Julia Evans
  • dockerfile (a)
    • multi-stage (b)
    • dockerignore (b)
    • distroless, scratch, alpine, slim (b)
    • CoW (a)
    • Caching (b) —
  • components: not
    • Docker Daemon
    • HTTP API
    • buildx
    • runc
    • containerd
  • Network types
    • bridge
    • none
    • host
    • ipip
    • mcvlan
  • volume
    • readonly `:ro`
    • `:z`
  • compose:
    • how compose works
    • dns servicek

Kubernetes

• Kubernetes SDK
  • https://github.com/kubernetes/apimachinery
  • https://github.com/kubernetes/client-go
  • informers
• Controller / Operator
  • controller-runtime
  • kubebuilder
  • operator-sdk
  • reconcile loop
  • k8s error checking
  • Finalizer
  • status
  • printable columns
  • default values / validations (tags)
• Admission / Mutation Webhook
• tests
  • k8s envtest
• OKD:
  • CoreOS
• The complete flow of creating a deployment
• Book: Kubernetes in action by Marka Luksa ( Part3 - especially chapter 11 understanding kubernetes internals )
• components (a)
  • kubelet, scheduler, kube-proxy
• api
  • api server
    • authN
    • authZ
    • mutation
      • what is it (b)
      • objects in k8s (c)
      • writing a custom webhook (c)
    • admission
      • what is it (b)
      • object in k8s (c)
      • writing a custom webhook (c)
    • etcd watch
    • api server watch
    • controller pattern
    • scheduling pipeline
    • extension:
      • AA
      • CRD
• etcd:
  • raft / consensus
  • watch
  • persistence
  • why not redis?
• cri
  • kubelet watch
  • cri grpc call
  • crio
  • oci
  • runc
  • workload
    • deployment, sts, daemonset (a)
    • sts features (b)
      • naming
      • pvc per pod
    • daemonset:
      • no count
      • not drain
      • even if node restart ??
  • probe
    • liveness, readiness (a)
    • startup probe (b)
• network:
  • kube-proxy, service
    • service (headless/none, clusterip, loadbalancer, node port, external name) (a)
    • endpoint (b)
    • endpointslice (c)
    • kube proxy iptables chains
  • cni (b)
    • cilium
  • ingress controller (b)
  • dns
    • kubelet dns, dnsPolicy
    • CoreDNS: learning CoreDNS book
  • life of a packet North south
  • life of a packet East West
• CSI:
  • Container Storage interface standard - this is the reference and standard not a very good resource for a newbie
  • How to write a Container Storage Interface (CSI) plugin - A thorough resource with easy to understand explanation
  • Concepts:
    • pv
    • pvc
    • provisioner
    • driver
    • a/d controller
    • csi attacher/resizer/snapshotter
    • Life of a PVC
    • kubelet fsGroup policy
    • kubelet selinux re-labeling
    • inline csi (c)
• Console
  • Console customization
  • Dynamic plugins

Automation

• concepts:
  • Reusable modules (roles, scripts, …)
  • Idempotency (know the concept in rest but not in ansible)
  • Remote parallel execution
  • Inventory and discovery
  • DSL
• Tools:
  • Ansible
    • roles (b)
    • playbook (a)
    • tasks (a)
    • inventory (a)
    • group vars(b)
    • env (a)
    • ansible.cfg (b)
    • callbacks (d)
    • plugins (c)
    • dynamic inventory (c)
    • writing a module (d)
    • ansible-galaxy (c)
    • raw (c)
    • handlers (c)
    • jinja (b)
  • Terraform (Terraform up and running)
    • state (a)
    • storage backend state (b)
    • modules (b)
    • locals, vs variab