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Showing entries 681–720 of 787 in this first collection.
Troubleshooting guide
A timed-out create may have worked: making retried writes safe
Three ways to avoid duplicate records when retrying a create, from provider idempotency keys to lookup and an attempt ledger, and what to do when none is possible.
Troubleshooting guide
Website form to Pipedrive: store first, match by email, create a linked lead, respect the limits
The order of calls, the API versions, the matching rule, the rate limits and the outage design for pushing a form enquiry into Pipedrive without losing it, and the lookup that keeps a lost reply from creating a second lead.
Troubleshooting guide
Keep a register of your integrations: what expires, what limits you and what gets retired
A one-page register of each outside service's credentials, owners, dates and limits, with documented examples of what ends and where to watch for notices.
Troubleshooting guide
Certbot renewal on your own server: dry run, schedule, reload hook and the old 30-day rule
How to check that Let's Encrypt renewal will work before the certificate expires, what actually schedules it, why the web server must reload, and why the renewal threshold changed.
Troubleshooting guide
Certificate validation fails: port 80, redirects, DNS challenges and rate limits
What the HTTP-01 challenge needs from your server, when the DNS-01 challenge is the right choice, and how failed attempts can lock you out for an hour or a week.
Troubleshooting guide
Terraform: read the plan like a diff, keep secrets out of state, and protect what holds data
How to read a plan before applying, what a saved plan file and state can expose, when a module is worth writing, and the limits of prevent_destroy and import.
Platform
Terraform: write the resources as code, review the plan, and keep state safe
What a Terraform module job covers, what a monthly drift review does, and the acceptance evidence for each: a reviewed plan, a clean post-apply plan and a state you can protect.
Inspectable example
Worked example: synthetic Terraform plan review notes
A labelled synthetic example: two plans of one small module in the real Terraform output format, with the reviewer's notes beside the lines that matter, showing how creates, a replacement, an in-place change and a sensitive value are explained before anyone applies.
Troubleshooting guide
Kubernetes pod will not start: CrashLoopBackOff and ImagePullBackOff are different problems
How to read container state, previous logs and events to tell a crashing container from an image that cannot be pulled, and which manifest or values change fits each.
Troubleshooting guide
Pods Running but not Ready, and rollouts that never finish: probes and the progress deadline
What liveness, readiness and startup probes each do, why a liveness probe can cause an outage, how a Deployment reports a stalled rollout, and how to roll back safely.
Platform
Kubernetes: find out whether the manifest, the image or the cluster is at fault
How to separate a Deployment problem you can fix in a manifest or Helm values from application bugs and cluster faults, and how a one-Deployment repair is accepted.
Troubleshooting guide
Moving a PostgreSQL database to a new server: dump, roles, restore and the cutover freeze
What pg_dump does and does not include, how to rehearse a restore, how roles and ownership affect it, and why writes must stop before the final dump.
Troubleshooting guide
Reading a cloud bill: where the money usually hides and what to check before deleting
A first pass through a cloud bill: group by service and usage type, compare months, look for idle volumes and addresses, and check use and back up before any removal.
Buyer collection
For a founder with one server and nobody who looks after it
Which fixed infrastructure jobs fit a founder running a VPS alone, in what order to consider them, and what you must hold yourself.
Buyer collection
For an agency that runs servers for clients
How an agency can use fixed, evidenced server jobs for client work without owning client credentials, and what to hand to the client and keep for yourself.
Collection
Bringing a server into good order: the sequence that avoids locking yourself out
An ordered path for a VPS that works but is not looked after: a way back, access and firewall, updates, a proper home for the app, logs, secrets and certificates, with the check that closes each step.
Troubleshooting guide
Compose starts your app before the database is ready: health checks and startup order
Why depends_on alone does not wait for a database, how a health check that tests the real connection path and the service_healthy condition prevent the start-up failure, and the restart and redeploy habits a single-VPS Compose stack needs.
Troubleshooting guide
Your container port is open to the internet even though ufw says it is closed
How Docker-published ports sit outside the rules ufw manages, how to bind a port to the loopback address, and how to prove from outside which ports a server really exposes.
Troubleshooting guide
A disk filling with logs: three sources, three different limits
Why container logs, the systemd journal and application files each need their own size limit, what the defaults are, which changes apply only to new containers, and how to test a rotation rule safely.
Troubleshooting guide
Turn off SSH passwords without locking yourself out: order, files and checks
The safe order for key-only SSH and a deny-by-default firewall, why the first value wins in sshd_config, how to read the effective settings, and what to keep open while you test.
Troubleshooting guide
Automatic security updates on Ubuntu: what is enabled, what is not, and the reboot question
How unattended-upgrades decides what to install, how to run a dry run, where it logs, why a package can install and still need a restart, and what an honest monthly review adds.
Troubleshooting guide
systemd service that will not stay up: restart rules, start limits and start types
Why a unit does not restart by default, how Restart, RestartSec and the start limits interact, what Type changes, and how to test a service by killing it.
Troubleshooting guide
Secrets in an env file? Protected alternatives on Compose, systemd and Kubernetes, and the rotation order
Why environment variables are a weak place for secrets, how Compose secrets, systemd credentials and Kubernetes Secrets differ, and a rotation order that does not take the app offline.
Inspectable example
Worked example: a synthetic Linux baseline verification sheet
A labelled synthetic sheet of the checks that prove key-only SSH, a deny-by-default firewall and automatic security updates, with the pass and fail reading for each row.
Troubleshooting guide
nginx 502 or 504? Read which stage failed before you change anything
Tell an upstream that refused the connection from one that answered too slowly, using the status code, the error log and the proxy settings that apply to the failing route.
Troubleshooting guide
nginx sends the wrong path upstream: proxy_pass URIs and location matching
Why one route returns 404 or the wrong page behind nginx: how a location is chosen, what proxy_pass does when it has a URI, and the cases where nginx cannot substitute the path.
Troubleshooting guide
nginx timeouts, retries and WebSockets: what the defaults do to slow requests
How proxy timeouts, upstream failure counting and retry settings interact, why a WebSocket drops after a minute of silence, and which change is safe for a slow endpoint.
Platform
nginx: separate the proxy, the application and the network before you change a setting
What nginx can fix for a site behind it, what only the application or the network can, and how a proxy repair is accepted: reproduce, test the configuration, reload, prove.
Inspectable example
Worked example: a synthetic nginx 502 and 504 triage matrix
A labelled synthetic case showing how log stage, direct request and configuration lines are compared to name a cause, with the before and after results a buyer should expect.
Collection
Gateway error behind nginx: the order to check, from status to fix
An ordered path from a visitor-reported 502 or 504 to a tested nginx change: who generated the error, which stage failed, which setting applies and how the fix is proved.
Troubleshooting guide
Designing a Webflow CMS collection: the template page, the address and the limits that matter
A collection page in Webflow is one template that produces a page for every item. This guide covers how it connects to fields, how the address is fixed, and the documented limits that shape the design.
Troubleshooting guide
Importing a spreadsheet into the Webflow or Wix CMS: field mapping, dates and what gets erased
A CMS import matches columns to fields without checking meaning. This guide lists the file limits, the Wix rule that unmapped fields are erased, and the traps in dates, links and images.
Troubleshooting guide
Members-only pages on Wix, Squarespace and Webflow: what each builder's own tools can and cannot do
Wix and Squarespace each have a built-in members feature with different rules. Webflow no longer has one. This guide sets out how each works and the limits worth knowing before you promise anyone privacy.
Troubleshooting guide
Bubble apps showing the wrong records: why hiding on the page is not protection
In Bubble, data reaches the browser unless a privacy rule on the data type stops it. This guide explains the rule settings that surprise people, the one-step limit on relationships and a safe two-account test.
Troubleshooting guide
Custom domain stuck on pending or showing a security warning on Webflow, Squarespace or Wix
A builder issues its HTTPS certificate only once your domain points at it cleanly. The usual blockers are leftover records, a CAA restriction, a proxy in front of the domain, DNSSEC and impatience.
Troubleshooting guide
Leaving Wix or Squarespace: what each builder will export and what you must rebuild
Neither builder gives a full export. This guide lists what each one will and will not let out, how the WordPress importer treats it, and why a move should start from a page list, not a file.
Troubleshooting guide
301 redirects on Webflow, Squarespace and Wix: what each tool accepts and how to test the whole list
A redirect map is only as good as the tool that loads it. This guide covers each builder's rules and limits, the mistakes that overwrite or loop, and how to test every old address.
Troubleshooting guide
Webflow form emails not arriving: find the stage that failed before changing anything
A Webflow form is stored first and emailed second. A labelled test on the published site shows which stage fails, and each stage has its own short list of causes.
Troubleshooting guide
Squarespace form submissions missing: storage options, one email address and what each limit does
A Squarespace form block saves submissions to the storage you choose and emails one address. Most missing submissions trace to a storage setting, an old address or a connection limit.
Troubleshooting guide
Wix form notifications: the automation behind the email and why its recipient goes stale
Wix emails form submissions through an automation. The recipient list lives there, not in the form, so changing an account email or a collaborator does not change who gets the message.