Network
How to Use SSH on Windows With OpenSSH and WSL the Safe Way
Use SSH on Windows with the built-in OpenSSH client, the agent service, key permissions, WSL with its separate keys, and the optional server.
6 min read
Topic
Network
SSH, curl, DNS, ports and HTTP APIs from the terminal, for when a connection or a request will not behave.
Network
How to Verify SSH Host Key Fingerprints With Examples
Verify an SSH host key fingerprint before trusting a server: read it on the server, compare the prompt, and use console output, SSHFP DNS or certificates.
6 min read
Python
How to Use jq Style Queries in Python on JSON With Examples
Query JSON in Python the way jq does: load, walk nested keys safely, filter lists, group and count, and handle missing keys without KeyError.
6 min read
Automation
How to Run a Command on Many Servers With pdsh or ssh
Run a command on many servers at once with pdsh, parallel ssh, xargs -P or GNU parallel, with host lists, output labels, timeouts and a failure summary.
6 min read
Network
How to Handle Time Zones and Timestamps in API Scripts
Handle API timestamps and time zones in scripts: ISO 8601 in UTC, epoch seconds versus milliseconds, GNU and BSD date, jq and daylight saving traps.
7 min read
Network
How to Upload and Download Large Files Through APIs
Upload and download large files through APIs with curl: stream, resume, retry, multipart and pre-signed URLs, size limits, checksums and progress.
7 min read
DevOps
How to Deploy From CI Over SSH and Avoid the Pitfalls
Deploy from CI over SSH with a dedicated key limited by authorized_keys options, a pinned host key, a single deploy command and no StrictHostKeyChecking off.
6 min read
Network
How to Use ssh keyscan and Manage known hosts Step by Step
Manage SSH known_hosts with ssh-keyscan: fetch host keys safely, verify fingerprints, hash entries, remove stale ones and use accept-new in automation.
6 min read
Network
How to Audit SSH Logins and Failed Attempts the Safe Way
Audit SSH logins on Linux: read auth logs and the journal, count failed attempts, list successful logins by key, spot invalid users and raise the log level.
6 min read
Network
How to Use Hardware Keys With SSH Without Surprises
Use a FIDO2 hardware key for SSH: generate an ed25519-sk key, choose resident or not, require touch and PIN, use it on new machines and keep a backup.
6 min read
Go
How to Write an SSH Client Script in Go With Examples
Write an SSH client in Go with golang.org/x/crypto/ssh: key or agent authentication, verified host keys through known_hosts, timeouts and running a command.
6 min read
Go
How to Write a Simple TCP Port Scanner in Go in Real Scripts
Write a simple concurrent TCP port scanner in Go with net.DialTimeout, a bounded worker pool, sorted results and notes on filtered versus closed ports.
6 min read
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