We generally use VPN (Virtual Private Network) to test whether content piece is accessible from another country. Using VPN our servers are tricked as if the request is coming from another country. How does this happen ?

On a simple level, when VPN app is running on my device it will send all my requests (app or browser requests) to the VPN server that is located in some another country. VPN server will then forward these requests to the destination server. Since the request has actually come from another country, destination server will respond. This response will then be forwarded back to me. Thus VPN has acted as a middle-man or proxy to send my request.

With scale, time becomes of essence in resolving an issue. Thus, identifying and resolving issues quickly becomes of essence. Collating data from multiple sources to debug an issue is not desirable in such case. If your workspace is on Slack, then getting alerts on Slack increases visibility and saves time in crisis (when it matters). Slack can also be used to send alerts of any background tasks like celery tasks, jenkins deployments, …

While development, we run Django application using python manage.py runserver. But that is not recommended for production use. Why so ?

Firstly, in development mode, lot of details are returned which expose internals of system. This is a security risk in production. Secondly, application doesn’t auto-restart if it crashes with some error. Memory leaks in application accumulate over time eventually leading to crashing of server. Load can’t be balanced across CPU cores. Then static files are served synchronously this would result in queuing of requests. In dev mode server runs as a single thread so it can’t handle multiple concurrent requests thus increasing overall response time. There isn’t connection pooling for database connections. Overall it is not a reliable setup that should be used in production.