A VPS that does nothing but still lights up its disk I/O counter is a common and frustrating problem. The writes are real, but the process responsible usually is not…
Read MorePreventing Silent Data Corruption with ZFS Checksums on a Low-RAM VPS
Silent data corruption is the failure nobody notices until a restore fails: a bit flips on a disk, the filesystem returns success, and your application reads plausible garbage for months….
Read MoreAuditing Cron Job Failures and Email Alerting on a Small VPS
Cron is the most common scheduler on a VPS and the easiest to forget. A typo in a path, an expired token, a full disk — and a backup or…
Read MoreTuning TCP Congestion Control on a High-Latency VPS: CUBIC vs BBR, Verified
On a WAN link with 100 ms or more of round-trip delay, a small VPS running the default CUBIC congestion control spends most of its time growing its window slowly…
Read MoreAuditing systemd Journal Disk Usage on a Small VPS: Measure, Cap and Verify
On a small VPS with a 20–40 GB disk, an unmanaged systemd journal is one of the most common causes of a surprise full filesystem. Unlike logrotate-driven text logs, the…
Read MoreCut VPS Boot Time to Under 10 Seconds: A systemd-analyze Workflow
A practical walkthrough of systemd-analyze blame and critical-chain: how to find the units that actually gate boot time and the fixes that cut it down.
Read MoreTuning Linux Kernel Entropy for High-Connection Servers
Why modern Linux CRNG rarely blocks in steady state, the boot-time stall that actually bites VMs, and how virtio-rng plus a persistent seed fixes it.
Read MoreZero-Downtime Service Reloads on a VPS: Connection Draining, SO_REUSEPORT and SIGQUIT Semantics
How to reload web services on a VPS without dropping connections: nginx SIGHUP semantics, worker_shutdown_timeout draining, SO_REUSEPORT, and a curl loop that proves zero failed requests.
Read MoreDiagnosing vm.max_map_count and mmap Exhaustion on a Small VPS
A VPS can refuse new memory mappings while free RAM is plentiful. Learn to read vm.max_map_count, count a process’s VMAs in /proc/PID/maps, and fix ENOMEM failures that are not about RAM.
Read MoreDiagnosing TLS Handshake Failures on a VPS with tcpdump and tshark
When a TLS handshake fails, the application log usually offers one line — handshake failure, no shared cipher, or a bare 400 in the access log — with no peer…
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