Services

Resources

Company

Our Work

Blog

How To

Back to Tags

Blogs

Illustration of a laptop and browser windows on a deep crimson background crossed with red circuit-like lines

Read Blog

How to fix the eMudhra CA compromise on macOS
Portrait of Saurabh Hirani, Principal SRE at One2N

Saurabh Hirani

Principal SRE @One2N

Portrait of Spandan Ghosh, Content at One2N

Spandan Ghosh

Content @One2N

How to fix the eMudhra CA compromise on a Mac: clean the CA bundles curl reads, update Node, Python, Go and Java, and prove each fix with a probe.

Illustration on a navy background of a terminal running exec 3<>/dev/tcp/host/443, cabled into a network socket, next to a dashed folder labelled /dev/tcp that does not exist

Read Blog

How to test TCP connectivity without curl using bash /dev/tcp
Portrait of Saurabh Hirani, Principal SRE at One2N

Saurabh Hirani

Principal SRE @One2N

No curl, wget or nc on a locked-down box? Use bash /dev/tcp to check if a port is open and read HTTP endpoints, and learn why it fails in zsh.

Cover illustration for Why your EKS Auto Mode NodeClass keeps reverting to default

Read Blog

Why your EKS Auto Mode NodeClass keeps reverting to default
Portrait of Ananya Dasgupta, SRE at One2N

Ananya Dasgupta

SRE @One2N

EKS Auto Mode reverted our default NodeClass after Argo CD synced secondary CIDR pod subnets. Why Auto Mode owns that object and what to change instead.

Cover illustration for OpenSearch Workload Management (WLM) for heavy search queries

Read Blog

OpenSearch Workload Management (WLM) for heavy search queries
Portrait of Srivatsa RV, SRE at One2N

Srivatsa RV

SRE @One2N

OpenSearch Workload Management puts heavy report queries and product search in separate workload groups with CPU, memory, timeout and shard limits.

Cover illustration for How to evaluate AI SRE agents for production?

Read Blog

How to evaluate AI SRE agents for production?
Portrait of Hemant Kumar, Staff SRE at One2N

Hemant Kumar

Staff SRE @One2N

How we evaluate AI SRE agents before they touch a production incident, applied to an OpenSRE v0.1 PoC and scored on how fast it helps isolate a fault.

Cover illustration for Conway's Law as a lever to fix legacy architectures

Read Blog

Conway's Law as a lever to fix legacy architectures
Portrait of Chinmay Naik, CEO at One2N

Chinmay Naik

CEO @One2N

Conway's law says architecture mirrors team communication. A shared policy database showed it; the Reverse Conway Maneuver helps refactor legacy systems.

Cover illustration for Hardening Kubernetes security with Istio ambient mode on flat networks

Read Blog

Hardening Kubernetes security with Istio ambient mode on flat networks
Portrait of Harshwardhan Mehrotra, SRE at One2N

Harshwardhan Mehrotra

SRE @One2N

Portrait of Spandan Ghosh, Content at One2N

Spandan Ghosh

Content @One2N

Istio Ambient mode on a flat EKS Hybrid network: how we rebuilt workload isolation with mTLS, SPIFFE identity, egress control and NetworkPolicies.

Cover illustration for Git was not built for multiple AI agents. Worktrees fix that.

Read Blog

Git was not built for multiple AI agents. Worktrees fix that.
Portrait of Srivatsa RV, SRE at One2N

Srivatsa RV

SRE @One2N

Portrait of Spandan Ghosh, Content at One2N

Spandan Ghosh

Content @One2N

Git worktrees for agentic development: give each AI coding agent its own folder and branch on one repo, so parallel chats stop fighting over one checkout.

Cover illustration for Multi-tenant SFTP: how we built a zero-ops setup on AWS Transfer Family

Read Blog

Multi-tenant SFTP: how we built a zero-ops setup on AWS Transfer Family
Portrait of Kshitish Deshpande, Software Engineer at One2N

Kshitish Deshpande

Software Engineer @One2N

Portrait of Spandan Ghosh, Content at One2N

Spandan Ghosh

Content @One2N

How One2N built a zero-ops multi-tenant SFTP system for a fintech client using AWS Transfer Family: one endpoint, isolated buckets, no manual server ops.

Cover illustration for My new laptop broke Slack. That's how I ended up on Bluefin.

Read Blog

My new laptop broke Slack. That's how I ended up on Bluefin.
Portrait of Harsh Mishra, SRE

Harsh Mishra

SRE

Portrait of Spandan Ghosh, Content at One2N

Spandan Ghosh

Content @One2N

A kernel patch broke Slack on my Dell XPS. Here's how that led me to Bluefin, immutable Linux, bootc, and OCI images and why it solved my problem for good.

Cover illustration for The gotchas of OTel Collector processors in Kubernetes

Read Blog

The gotchas of OTel Collector processors in Kubernetes
Portrait of Sanket Rajgiri, SRE at One2N

Sanket Rajgiri

SRE @One2N

Portrait of Spandan Ghosh, Content at One2N

Spandan Ghosh

Content @One2N

OTel Collector processor gotchas in Kubernetes: batching to stop 429s, crashes in spikes, noise filters, k8s enrichment, sampling and two-tier collectors.

Cover illustration for How queueing theory makes systems reliable

Read Blog

How queueing theory makes systems reliable
Portrait of Srivatsa RV, SRE at One2N

Srivatsa RV

SRE @One2N

Queueing theory for SREs: the M/M/1 model shows why 70% utilisation feels calm and 90% collapses under spikes, and why headroom is insurance, not waste.

Cover illustration for How to read SRE graphs without lying to yourself

Read Blog

How to read SRE graphs without lying to yourself
Portrait of One2N, Team

One2N

Team

How to read SRE graphs honestly: averages that hide pain, sampling windows that erase spikes, log scales and heatmaps, plus a checklist for incidents.

Cover illustration for Error budget calculation: downtime minutes for every SLO

Read Blog

Error budget calculation: downtime minutes for every SLO
Portrait of Srivatsa RV, SRE at One2N

Srivatsa RV

SRE @One2N

Error budget calculation from your SLO: 99.9% over 30 days is 43 minutes of downtime, 99.95% is 21m 54s. Use burn rate to decide when to ship or pause.

Cover illustration for Percentiles in SRE: Why averages lie about latency

Read Blog

Percentiles in SRE: Why averages lie about latency
Portrait of Srivatsa RV, SRE at One2N

Srivatsa RV

SRE @One2N

Portrait of Spandan Ghosh, Content at One2N

Spandan Ghosh

Content @One2N

Percentiles in SRE: 50 slow requests in 1,000 can leave average latency near 200 ms. How p50, p95 and p99 expose tail latency and which ones to monitor.

Cover illustration for Latency vs throughput: why high utilisation hurts reliability

Read Blog

Latency vs throughput: why high utilisation hurts reliability
Portrait of Srivatsa RV, SRE at One2N

Srivatsa RV

SRE @One2N

Portrait of Spandan Ghosh, Content at One2N

Spandan Ghosh

Content @One2N

Latency vs throughput explained for engineers: how the two interact with utilisation, and why running at 90 percent capacity quietly wrecks your SLOs.

Cover illustration for Deploying a scalable NATS cluster part 2: hands-on demo

Read Blog

Deploying a scalable NATS cluster part 2: hands-on demo
Portrait of Barun Debnath, SRE

Barun Debnath

SRE

Portrait of Spandan Ghosh, Content at One2N

Spandan Ghosh

Content @One2N

Deploy a four-node NATS cluster with Docker, JetStream stream replication, dead letter queues and Prometheus and Grafana dashboards, then load test it.

Cover illustration for SRE math every engineer should know: a practical guide

Read Blog

SRE math every engineer should know: a practical guide
Portrait of Srivatsa RV, SRE at One2N

Srivatsa RV

SRE @One2N

SRE math for on-call engineers: percentiles that averages hide, Little's Law, error budgets as downtime minutes, queueing theory and honest graph reading.

Cover illustration for Debugging KubeVPN's DNS resolution failures

Read Blog

Debugging KubeVPN's DNS resolution failures
Portrait of Nilesh D, Software Engineer at One2N

Nilesh D

Software Engineer @One2N

Portrait of Chinmay Naik, CEO at One2N

Chinmay Naik

CEO @One2N

Debugging KubeVPN DNS on macOS: go.dev failed to resolve because KubeVPN sent it to a dev namespace. scutil --dns found it; resetting adapter DNS fixed it.

Cover illustration for What happens when you run Terraform commands?

Read Blog

What happens when you run Terraform commands?
Portrait of Sahil Joseph, Staff SRE at One2N

Sahil Joseph

Staff SRE @One2N

Portrait of Saurabh Hirani, Principal SRE at One2N

Saurabh Hirani

Principal SRE @One2N

What happens when you run Terraform commands: how Terraform core talks to provider plugins over gRPC, credential handling, state locking and debugging.

Cover illustration for Daily driving Omarchy and Hyprland as a CTO

Read Blog

Daily driving Omarchy and Hyprland as a CTO
Portrait of Jaideep Khandelwal, CTO at One2N

Jaideep Khandelwal

CTO @One2N

A CTO's review of daily driving Omarchy, DHH's Arch-based Linux with Hyprland preconfigured, after macOS: what works, what breaks and who should use it.

Cover illustration for A pragmatic guide to get started with OpenTelemetry

Read Blog

A pragmatic guide to get started with OpenTelemetry
Portrait of Spandan Ghosh, Content at One2N

Spandan Ghosh

Content @One2N

A pragmatic OpenTelemetry guide for SREs: monitoring vs observability, logs, metrics and traces, OTel instrumentation, and strategies to migrate backends.

Cover illustration for How we solved a critical site-to-site VPN IP address conflict in AWS

Read Blog

How we solved a critical site-to-site VPN IP address conflict in AWS
Portrait of Rishiraj Rathore, SRE at One2N

Rishiraj Rathore

SRE @One2N

Portrait of Spandan Ghosh, Content at One2N

Spandan Ghosh

Content @One2N

A site-to-site VPN in AWS came up but every request timed out: both sides used 10.0.0.0/22. Why a secondary CIDR failed and the parallel setup that worked.

Cover illustration for Deploying a scalable NATS cluster, part 1: core architecture

Read Blog

Deploying a scalable NATS cluster, part 1: core architecture
Portrait of Barun Debnath, SRE

Barun Debnath

SRE

NATS cluster architecture, part 1: pub-sub and queue groups, JetStream persistence, cluster, super cluster and leaf node topologies, and what to plan for.

Cover illustration for GitHub runners fundamentals and self-hosted runner setup

Read Blog

GitHub runners fundamentals and self-hosted runner setup
Portrait of Rajesh Jangid, SRE

Rajesh Jangid

SRE

Portrait of Spandan Ghosh, Content at One2N

Spandan Ghosh

Content @One2N

What GitHub runners are, how GitHub-hosted and self-hosted runners differ, and how to set up a self-hosted GitHub Actions runner.

Cover illustration for All software is assembled

Read Blog

All software is assembled
Portrait of Chinmay Naik, CEO at One2N

Chinmay Naik

CEO @One2N

All software is assembled: why teams ship faster by integrating third-party components than building from scratch, and how to treat dependencies.

Cover illustration for EKS upgrade best practices: how to upgrade EKS clusters safely

Read Blog

EKS upgrade best practices: how to upgrade EKS clusters safely
Portrait of Aashi Rathore, SRE at One2N

Aashi Rathore

SRE @One2N

Portrait of Spandan Ghosh, Content at One2N

Spandan Ghosh

Content @One2N

EKS upgrade checklist from our v1.23 to v1.30 move: control plane checks, VPC CNI, CoreDNS and kube-proxy add-ons, Velero backups and node group upgrades.

Cover illustration for AWS SSM port forwarding to private EC2 without SSH or bastions

Read Blog

AWS SSM port forwarding to private EC2 without SSH or bastions
Portrait of Harsh Mishra, SRE

Harsh Mishra

SRE

AWS SSM port forwarding to EC2 in private subnets with Session Manager, with no open SSH port or bastion. Covers the IAM role, SSM Agent and endpoints.

Cover illustration for Gotchas to avoid when using AWS spot instances in production

Read Blog

Gotchas to avoid when using AWS spot instances in production
Portrait of Aashi Rathore, SRE at One2N

Aashi Rathore

SRE @One2N

Portrait of Spandan Ghosh, Content at One2N

Spandan Ghosh

Content @One2N

AWS spot instances in production on EKS: two-minute termination notices, ignored PodDisruptionBudgets, slow replacement capacity and a real outage we had.

Cover illustration for Accessing private EC2 Instances without keys or passwords

Read Blog

Accessing private EC2 Instances without keys or passwords
Portrait of Adarsh Raj, SRE

Adarsh Raj

SRE

Portrait of Spandan Ghosh, Content at One2N

Spandan Ghosh

Content @One2N

Access private EC2 instances without SSH keys or passwords using AWS Systems Manager Session Manager: no public IPs, no inbound rules, and no shared keys.

Cover illustration for Using UTM and Vagrant for dev environments on Apple Silicon

Read Blog

Using UTM and Vagrant for dev environments on Apple Silicon
Portrait of Srivatsa RV, SRE at One2N

Srivatsa RV

SRE @One2N

Portrait of Spandan Ghosh, Content at One2N

Spandan Ghosh

Content @One2N

VirtualBox no longer supports M-series Macs. How to run Vagrant with UTM to spin up reproducible local dev environments on Apple Silicon, tested on an M3.

Cover illustration for Karpenter vs Cluster Autoscaler for Kubernetes node scaling

Read Blog

Karpenter vs Cluster Autoscaler for Kubernetes node scaling
Portrait of Rahul H Bhatia, SRE

Rahul H Bhatia

SRE

Portrait of Spandan Ghosh, Content at One2N

Spandan Ghosh

Content @One2N

Karpenter vs Cluster Autoscaler: how each scales Kubernetes nodes, from predefined node groups and priority expanders to provisioning and cost trade-offs.

Cover illustration for Exploring RAG: enhancing LLMs with external knowledge

Read Blog

Exploring RAG: enhancing LLMs with external knowledge
Portrait of Harsh Mishra, SRE

Harsh Mishra

SRE

Portrait of Saurabh Hirani, Principal SRE at One2N

Saurabh Hirani

Principal SRE @One2N

Retrieval augmented generation (RAG) for engineers: LLM basics, where standalone models fall short, and the parts of a RAG app such as embeddings.

Cover illustration for ClickHouse schema optimization for sparse data sets

Read Blog

ClickHouse schema optimization for sparse data sets
Portrait of Amit Sadafule, Lead Software Engineer

Amit Sadafule

Lead Software Engineer

Portrait of Spandan Ghosh, Content at One2N

Spandan Ghosh

Content @One2N

Portrait of Saurabh Hirani, Principal SRE at One2N

Saurabh Hirani

Principal SRE @One2N

Portrait of Chinmay Naik, CEO at One2N

Chinmay Naik

CEO @One2N

Schema designs for storing and querying sparse data sets in ClickHouse, including a sparse matrix and separate tables, and when each one fits.

Cover illustration for Setting up CloudWatch alerts for EKS clusters: insights and solutions

Read Blog

Setting up CloudWatch alerts for EKS clusters: insights and solutions
Portrait of Mihir Bhagwat, SRE at One2N

Mihir Bhagwat

SRE @One2N

Portrait of Saurabh Hirani, Principal SRE at One2N

Saurabh Hirani

Principal SRE @One2N

Portrait of Spandan Ghosh, Content at One2N

Spandan Ghosh

Content @One2N

CloudWatch alerts for EKS node readiness with Container Insights: per-node alarms for static nodes, then Metric Insights and MIN(MIN) for autoscaled ones.

Cover illustration for How we used Fly.io to improve a Pipecat-AI chatbot

Read Blog

How we used Fly.io to improve a Pipecat-AI chatbot
Portrait of Ajinkya Wadekar, SRE at One2N

Ajinkya Wadekar

SRE @One2N

Portrait of Spandan Ghosh, Content at One2N

Spandan Ghosh

Content @One2N

A Pipecat-AI chatbot on ECS hit limits at 10 to 15 chat rooms per task, and 6GB images slowed scale-up. How Fly.io machines spun from containers fixed it.

Cover illustration for How to use multiple GitHub accounts on one machine

Read Blog

How to use multiple GitHub accounts on one machine
Portrait of Saurabh Hirani, Principal SRE at One2N

Saurabh Hirani

Principal SRE @One2N

Use multiple GitHub accounts on one machine: a separate SSH key per account, SSH host entries, and includeIf in your Git config to pick the right identity.

Cover illustration for Understanding MLOps from a software engineers' perspective

Read Blog

Understanding MLOps from a software engineers' perspective
Portrait of Harsh Mishra, SRE

Harsh Mishra

SRE

Portrait of Spandan Ghosh, Content at One2N

Spandan Ghosh

Content @One2N

Portrait of Chinmay Naik, CEO at One2N

Chinmay Naik

CEO @One2N

Portrait of Jaideep Khandelwal, CTO at One2N

Jaideep Khandelwal

CTO @One2N

MLOps for software engineers is DevOps plus data engineering and ML. The MLOps lifecycle, knowledge silos, automation, versioning and experiment tracking.

Cover illustration for Database schema migrations: a practical guide to managing schema changes

Read Blog

Database schema migrations: a practical guide to managing schema changes
Portrait of Spandan Ghosh, Content at One2N

Spandan Ghosh

Content @One2N

Database schema migrations without manual steps: versioned migrations, running them in every deploy, and tools like Flyway, Liquibase and ORM migrations.

Cover illustration for Multi-tenant authorization in Go with Permify for B2B SaaS

Read Blog

Multi-tenant authorization in Go with Permify for B2B SaaS
Portrait of Mohit Kumar, Software Engineer

Mohit Kumar

Software Engineer

Multi-tenant authorization in Go with Permify, an open-source Zanzibar-based engine: our RBAC model, the schema, and how services call Permify over gRPC.

Cover illustration for Achieving CI/CD with previews for your static website hosted on S3

Read Blog

Achieving CI/CD with previews for your static website hosted on S3
Portrait of Drasti Kaurav, SRE at One2N

Drasti Kaurav

SRE @One2N

CI/CD for a static website on S3 with preview environments: automated builds and deploys without developer AWS keys, plus CloudFront cache invalidation.

Cover illustration for Making your Go CLI binaries self-updatable

Read Blog

Making your Go CLI binaries self-updatable
Portrait of Sitaram Shelke, SRE

Sitaram Shelke

SRE

Make Go CLI binaries self-updatable without brew or apt: fetch the latest release, download the binary for the OS and architecture, and apply the update.

Cover illustration for Exposing SaaS APIs privately to customers with AWS PrivateLink

Read Blog

Exposing SaaS APIs privately to customers with AWS PrivateLink
Portrait of Siddharth Mishra, SRE

Siddharth Mishra

SRE

Expose SaaS API endpoints privately with AWS PrivateLink, not VPC peering, which breaks on overlapping CIDRs. Same-region latency fell from 0.21s to 0.08s.

Cover illustration for AWS SSO with the Go SDK: making SSO auth work in Golang

Read Blog

AWS SSO with the Go SDK: making SSO auth work in Golang
Portrait of Chinmay Somani, SRE

Chinmay Somani

SRE

Why AWS SSO profiles fail with the AWS SDK for Go v1, and the two fixes: change your ~/.aws/config, or upgrade to the v2 SDK.

Cover illustration for Automate RDS secret management using AWS Secrets Manager

Read Blog

Automate RDS secret management using AWS Secrets Manager
Portrait of Siddharth Shashikar, SRE at One2N

Siddharth Shashikar

SRE @One2N

Manage and rotate RDS credentials with AWS Secrets Manager: compare ways to store RDS secrets, then automate creation and rotation with Terraform.

Cover illustration for Moving from traditional CD pipelines to GitOps

Read Blog

Moving from traditional CD pipelines to GitOps
Portrait of Jaideep Khandelwal, CTO at One2N

Jaideep Khandelwal

CTO @One2N

Moving from traditional CD pipelines to GitOps: shared Jenkins credentials and cross-environment access, GitOps principles, and how we adopted Flux CD.

Cover illustration for Kubernetes HPA on external metrics with Prometheus Adapter

Read Blog

Kubernetes HPA on external metrics with Prometheus Adapter
Portrait of Akshay Srivastava, SRE at One2N

Akshay Srivastava

SRE @One2N

Kubernetes HPA on external metrics: scaling pods on Redis queues from a server outside the cluster with Prometheus Adapter, plus CPU and memory metrics.

Cover illustration for Implementing a real-time analytics engine using big data principles

Read Blog

Implementing a real-time analytics engine using big data principles
Portrait of Jaideep Khandelwal, CTO at One2N

Jaideep Khandelwal

CTO @One2N

A real-time analytics engine for 50 million data points: replacing a MySQL setup with 48-hour query delays with Apache Spark pipelines and data marts.

Cover illustration for Mock API in microservices architecture

Read Blog

Mock API in microservices architecture
Portrait of Kalpesh Deo, Staff software engineer-II at One2N

Kalpesh Deo

Staff software engineer-II @One2N

Mock APIs in microservices architecture: why running every dependent service locally slows developers down, and how mocks unblock local dev and testing.

Cover illustration for Centralized VPN solutions for cloud and on-premise

Read Blog

Centralized VPN solutions for cloud and on-premise
Portrait of Sagar Rakshe, SRE

Sagar Rakshe

SRE

A centralized VPN for cloud and on-premise networks: how a Pritunl cluster replaced shared OpenVPN profiles and cut a client's VPN issues by more than 90%.

Cover illustration for Homogenous build setups for local and CI workflows

Read Blog

Homogenous build setups for local and CI workflows
Portrait of Sitaram Shelke, SRE

Sitaram Shelke

SRE

Homogenous build setups give local and CI one interface to build and test. How we used Makefiles and Bash with Jenkins so builds match everywhere.

Talks

Thumbnail for the talk Using LLMs to Improve Incident Response Times | mitramandal.ai - 2025

Watch Talk

Using LLMs to Improve Incident Response Times | mitramandal.ai - 2025
Portrait of Jaideep Khandelwal, CTO at One2N

Jaideep Khandelwal

CTO @One2N

A talk from mitramandal.ai, One2N's AI meetup, on using LLMs to improve incident response times in real engineering workflows.

Thumbnail for the talk Sshuttle, poor man's VPN - Devops Days Bangalore 2023

Watch Talk

Sshuttle, poor man's VPN - Devops Days Bangalore 2023
Portrait of Jaideep Khandelwal, CTO at One2N

Jaideep Khandelwal

CTO @One2N

A lightning talk on sshuttle: a transparent proxy that works as a lightweight VPN, forwards over SSH, needs no admin, and supports DNS tunneling.

Thumbnail for the talk Making your cli self Updateable

Watch Talk

Making your cli self Updateable
Portrait of Shubham Rasal, SRE

Shubham Rasal

SRE

How to make Go binaries self-updatable using Minio's self-update library, with real examples from ProjectDiscovery and Cloudlens.

Thumbnail for the talk How to navigate unknown codebases

Watch Talk

How to navigate unknown codebases
Portrait of Chinmay Naik, CEO at One2N

Chinmay Naik

CEO @One2N

How to navigate an unknown codebase, using a todo app (Ultralist) as the example, with practical takeaways for exploring unfamiliar code.

Thumbnail for the talk Learn REST API design - OTP based Auth API

Watch Talk

Learn REST API design - OTP based Auth API
Portrait of Chinmay Naik, CEO at One2N

Chinmay Naik

CEO @One2N

Learn REST API design with a real-world example: we build an OTP-based auth API with signup, login, send-otp and validate-otp endpoints.

‹ Go

Incident Management ›