MajorLinux
9b066d0e54
New 05-troubleshooting/networking article covering the case where ssh <alias> fails host-key verification because no Host block exists and the alias resolves via Tailscale MagicDNS to a name with no known_hosts entry (key stored under the IP). Registered in SUMMARY.md and the troubleshooting index.
3.9 KiB
3.9 KiB
| created | updated |
|---|---|
| 2026-03-15T06:37 | 2026-05-02T17:50 |
🔧 General Troubleshooting
Practical fixes for common Linux, networking, and application problems.
🖥️ GPU & AI
- Qwen2.5-14B OOM on RTX 3080 Ti (12GB)
- LoRA adapter — GGUF conversion fails with 'config.json not found'
🌐 Networking & Web
- Apache Outage: Fail2ban Self-Ban + Missing iptables Rules
- Mail Client Stops Receiving: Fail2ban IMAP Self-Ban
- firewalld: Mail Ports Wiped After Reload
- Dovecot IMAP Clients Fail to Sync: vsz_limit OOM from a Bloated Index Log
- Postfix header_checks Can't Act on Milter-Added Headers (Use Sieve)
- Dovecot Phantom Mailboxes from .dovecot.lda-dupes (mail_home Overlapping the Maildir Root)
- Tailscale SSH: Unexpected Re-Authentication Prompt
- SSH Alias Falls Through to MagicDNS — Host-Key Verification Failure (No
HostBlock) - iOS Tailscale Clients Report HostName="localhost" — Breaks /etc/hosts Generators
- rsync over Tailscale: Hung in TCP Teardown After Transfer Completes
- Windows OpenSSH: WSL Default Shell Breaks Remote Commands
- Pi-hole AI Blocklist Blocks Claude Desktop (ERR_CONNECTION_REFUSED)
- ISP SNI Filtering & Caddy
- yt-dlp YouTube JS Challenge Fix
- wget/curl: URLs with Special Characters Fail in Bash
⚙️ Ansible & Fleet Management
- SSH Timeout During dnf upgrade on Fedora Hosts
- Vault Password File Missing
- ansible.cfg Ignored on WSL2 Windows Mounts
- regex_search — capture-group argument doesn't work in set_fact
📦 Docker & Systems
- Docker & Caddy Recovery After Reboot (Fedora + SELinux)
- Gitea Actions Runner: Boot Race Condition Fix
- Systemd Session Scope Fails at Login (
session-cN.scope) - MajorWiki Setup & Publishing Pipeline
- Cron Heartbeat False Alarm: /var/run Cleared by Reboot
🔒 SELinux
- SELinux: Fixing Dovecot Mail Spool Context (/var/vmail)
- SELinux: Wrong /etc/localtime Label Silently Breaks Timezone Changes