System Design · Senior · Question 75 of 75

Why can sticky routing of WebSocket users to a server complicate deploys?

✓Correct answer: Restarting a server drops all its connections at once; deploys must drain connections gradually and clients must reconnect with backoff
2WebSockets can't be load balanced
3Sticky routing disables TLS

Explanation

Connection draining and spreading reconnects avoid sudden load spikes on the remaining servers.

Further reading

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