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An application working inside a container is not automatically ready for the public Internet. It still needs a domain, TLS, HTTP-to-HTTPS redirects, persistent certificate storage, and a reverse proxy in front.
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OFFSET 100000 looks harmless, but the database may still have to find and discard a large number of records before returning a few dozen. While a user moves between pages, new data can also arrive at the front, causing an item to appear twice or disappear from the reading journey.
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The API still returns HTTP 200, yet the frontend suddenly fails because a field disappeared, changed type, or became null. Backend unit tests may remain green and Swagger UI may still load, but the contract consumers rely on has been broken.
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Feature flags separate deploying code from releasing behavior. A team can ship disabled code, expose it internally, increase the audience gradually, and turn it off during an incident without another build. Without lifecycle discipline, however, flags become permanent configuration and make every code path harder to understand.
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A short-lived access token limits the useful lifetime of a leak, but a refresh token is a long-lived credential that can mint new access tokens. If a backend accepts the same refresh token repeatedly, a stolen copy can preserve access quietly. Refresh token rotation replaces the credential after every use and detects replay of an older token.
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Ultra Wideband (UWB) is a short-range radio technology optimized for measuring distance and relative position between devices. Instead of merely inferring proximity from signal strength, UWB measures signal travel time. Compatible devices can therefore determine precise distance and, in some configurations, direction.
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An unpatched server is a security risk, but uncontrolled updates can cause an outage. unattended-upgrades lets Ubuntu Server install patches according to policy. Production environments still need restricted package sources, preflight validation, outcome monitoring, and a deliberate reboot process.
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A load average of 20 does not automatically mean 100% CPU usage. Linux load includes tasks running or waiting for CPU and tasks in uninterruptible sleep, often waiting for I/O. A high-load server may be constrained by CPU, disks, NFS, memory reclaim, a hypervisor, or another kernel path.
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“Cannot reach the server” can describe dozens of failures: a down interface, wrong address, missing default route, incorrect DNS, a service bound only to localhost, dropped packets, wrong TLS SNI, or a stalled upstream behind a proxy. Running random commands usually adds noise.
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n8n connects APIs, webhooks, schedules, and applications into automated workflows. Self-hosting gives control over data and infrastructure, but it also makes you responsible for secrets, backups, HTTPS, upgrades, and recovery.
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