Troubleshooting – Jean's Blog

ZFS Disaster Recovery: Rebuilding and Mirroring a Pool After Top-Level Vdev Error

I recently learned a hard lesson about ZFS Vdev architecture after attempting to convert a single-disk pool into a mirror. By mistake, I added the new disk as a top-level Vdev, rather than attaching it as a mirror. As zpool remove and zpool detach both failed on the top-level Vdev, I was forced to destroy the pool and restore the data from a snapshot.

This process outlines how I recovered data and subsequently created a proper mirror configuration.

Nextcloud S3 Workaround: Multi-User Rclone Mounts with Systemd Templates

I experienced trouble with Nextcloud’s built-in S3 connector, as it would corrupt photos during auto-upload from the Android client. Since dedicated S3FS or Goofys were also not ideal, I decided on a reliable alternative: using rclone to manage the mounts. This strategy allows me to decouple the unreliable Nextcloud S3 implementation from the underlying object storage.

Docker Update Automation: Advanced Bash Pipelining. paperless-ngx

This article documents a reliable update script for the Paperless-NGX stack, which minimizes the risk of container failures during automated maintenance. The focus here is not just on simple automation, but on ensuring the integrity of the process—especially handling logs and exit codes within complex Bash pipelines.

Suricata Performance: Resolving eBPF Bypass Failure via Manual Kernel Filter Compilation

Enabling eBPF (Extended Berkeley Packet Filter) bypass is the ultimate step in Suricata performance tuning. It allows the kernel to filter known-safe traffic (e.g., TLS data) before the packets reach the resource-intensive Userspace engine. However, this functionality often fails to work out-of-the-box.

Suricata IPS: Fixing Legitimate Traffic Drops by Disabling drop-invalid

I encountered a peculiar issue where my WordPress instance was unable to reach wordpress.org, and DokuWiki could not access its plugin repository. All standard network checks (wget, curl, DNS) worked fine, and no drops were registered by the standard firewall rules.

However, logging revealed a problem deep within the Intrusion Prevention System (IPS) layer.

Suricata AF-Packet: Resolving VirtIO Non-Functionality via Checksum Offload Disablement

This article documents a two-part process: successfully upgrading Suricata to version 7 on Debian Bookworm and solving a critical stability issue required to run the AF-Packet IPS mode with high-performance VirtIO NICs in a virtual machine. Without this specific configuration, the IPS failed to function.

Distributed MinIO on AWS Lightsail: Multi-Node Setup

MinIO is a high-performance, S3-compatible object storage solution. This article provides a blueprint for deploying a distributed MinIO stack using Amazon Lightsail, covering the critical steps for multi-node setup, networking, and Systemd.