Voxfor Magazine.

AI & Machine Learning

Qdrant Disk Sizing Must Include Optimizer Working Space

Raw vector bytes are only the first line in a Qdrant storage budget. A collection also carries payload, payload indexes, vector indexes,…

Aug 3, 20269 min read

Windows

Which VSS Writer Broke Your Windows Server Backup?

A failed VSS writer name is a lead, not a root cause. Preserve the backup timestamp, capture writer state, correlate application and…

Aug 3, 202610 min read

Database

PostgreSQL XID Age Is Rising: Find What Autovacuum Cannot Freeze

PostgreSQL transaction IDs are a countdown, not a disk-usage gauge. Every transaction that needs an XID advances a 32-bit counter. Vacuum protects…

Aug 3, 202611 min read

Linux

What Broke When NFS Returns a Stale File Handle?

Stale file handle is an identity error, not a generic network outage. The NFS client is presenting a server-issued handle for a…

Aug 3, 202610 min read

Security

Fail2ban Is Banning Your Proxy, Not the Attacker

A Fail2ban ban can look successful while blocking nothing. Behind Cloudflare or another reverse proxy, the web server may receive the proxy…

Aug 3, 202611 min read

DevOps

When etcd Raises NOSPACE, Compact Before You Defragment

An etcd NOSPACE alarm means at least one member's backend crossed its configured quota, so the cluster entered limited-operation maintenance mode. Reads…

Aug 3, 202611 min read

DevOps

Immich Backups Need More Than the Automatic Database Dump

Immich can create automatic PostgreSQL dumps, but those files do not contain the photos and videos people expect to recover. A usable…

Aug 3, 20269 min read

Security

Rotate SSH Host Keys Without Locking Out VPS Access

Do not overwrite active SSH host-key files in one step. Generate replacement keys under new filenames, load old and new identities together,…

Aug 3, 20269 min read

DevOps

Docker Build Cache Is Filling Your VPS: Reclaim Space Safely

If repeated Docker builds are consuming VPS storage, do not begin with a system-wide prune. First prove that BuildKit owns the missing…

Aug 3, 20269 min read

AI & Machine Learning

Why Ollama Uses CPU Even When Your GPU Is Available

nvidia-smi can show a healthy GPU while an Ollama request still runs partly—or entirely—on CPU. That contradiction does not have one universal…

Aug 3, 202610 min read

DevOps

Which Prometheus Label Is Multiplying Your Time Series?

A Prometheus server can run out of memory even when scrape traffic, retention and disk use look ordinary. The hidden multiplier is…

Aug 3, 20269 min read

Database

MySQL Replica Lag: Separate Receive Delay from Apply Delay

Two replicas can both report Seconds_Behind_Source: 0 while only one is current. On the healthy replica, the receiver has fetched the source's…

Aug 3, 20269 min read

Wordpress Issues

Why Are WordPress Requests Waiting for PHP-FPM Workers?

server reached pm.max_children means a PHP-FPM pool used every permitted child process at least once. It does not prove that the limit…

Aug 3, 202611 min read

DevOps

A RabbitMQ Disk Alarm Can Block Every Publisher

A RabbitMQ node can be running, answering health checks and delivering messages to consumers while every publishing connection is stalled. That split…

Aug 3, 202610 min read

Linux

Linux Conntrack Is Full While Existing Sessions Still Work

One SSH session remains responsive, a database connection keeps serving queries, yet every fresh health check times out. That combination can look…

Aug 3, 202611 min read

Security

DKIM Key Rotation Needs Two Selectors, Not a DNS Swap

A safe DKIM key rotation is an overlap between two selector names, not an in-place replacement of one DNS value. Publish and…

Aug 3, 202614 min read

Security

DNSSEC SERVFAIL: Find the Broken DS, DNSKEY, or RRSIG

SERVFAIL is frustrating because it names a result, not an owner. The fastest useful split is a paired query against the same…

Aug 3, 202611 min read

Linux

When an LVM Thin Pool Fills Up, Free Space Is Not the Whole Recovery

An LVM thin pool can fail while a filesystem still reports free space, because pool data blocks, pool metadata, volume-group extents and…

Aug 3, 20269 min read

DevOps

Before You Drain a Kubernetes Node, Prove the Workload Can Move

A Kubernetes node drain is safe only when the workload can complete four separate moves: the Eviction API may remove the Pod,…

Aug 3, 202611 min read

Linux

Was It the Kernel or systemd-oomd? Trace a Linux OOM Kill

Two services can end with the same SIGKILL, yet require opposite repairs. A global kernel OOM event means the host could not…

Aug 3, 202613 min read

Security

Keycloak Login Redirects Break Behind a Reverse Proxy

Broken Keycloak redirects behind a TLS-terminating reverse proxy usually mean that three URL owners disagree: Keycloak's public hostname, the proxy's forwarded request…

Aug 3, 202610 min read