SSSidharth Shambuinshambu2k.hashnode.dev·Jun 11 · 7 min readA bastion with no open portsI needed to reach a private Postgres database from my laptop, so I built a little bastion to tunnel through. The interesting thing about it is that it has no open ports at all. Nothing listens for inb00
SSSidharth Shambuinshambu2k.hashnode.dev·Nov 15, 2025 · 9 min readHow to share Nvidia GPUs that don’t support MIG and when vGPU isn’t an optionI recently had to build a system to share two Nvidia L40S GPUs (each with 48 GB of memory) among a group of users. The L40S does not support MIG (Multi-instance GPU) as it was designed as a PCIe-only GPU. Therefore, hardware slicing an individual GPU...00
SSSidharth Shambuinshambu2k.hashnode.dev·Oct 7, 2025 · 5 min readUsing Google OAuth to ssh into my serverTL;DR I put an experimental SSH3 server on a separate hostname, kept my normal SSH v2 behind Cloudflare Tunnel, and logged in with Google using OpenID Connect. SSH3 runs over HTTP/3 on UDP 443, supports a secret URL path, and can mint certs with Let’...00
SSSidharth Shambuinshambu2k.hashnode.dev·Feb 6, 2025 · 3 min readJupyterhub + Nginx InstallationPrerequisites Ubuntu server (x86_64 architecture) Root access Domain name pointing to server IP SSL certificates (recommend Let's Encrypt) Basic firewall configuration (ports 80/443 open) Python Installation apt update && apt install python3 ...00
SSSidharth Shambuinshambu2k.hashnode.dev·Jan 30, 2025 · 3 min readCORS IssuesThis blog is a repost of an internal company document I shared while I was at Cashfree Payments. It was part of a tech chit chat session. What is CORS? CORS stands for Cross-Origin Resource Sharing. It is a mechanism that allows restricted resources...00
