majorlinux
950759da52
New troubleshooting/networking article covering the three SSH failure modes after a fleet migration (stale hardcoded IP, Tailscale 1.98.x cold-path teardown, rebuilt-box host-key mismatch) and the durable fix (MagicDNS names + known_hosts purge + ConnectTimeout), with the WSL2 no-resolver caveat. Cross-links the existing host-key article (adds a 'when pinning the IP is wrong' callout) and adds the SUMMARY nav entry.
15 KiB
15 KiB
| created | updated |
|---|---|
| 2026-04-02T16:03 | 2026-05-15T09:00 |
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--prune-profilesTrap and How to Recover - Mastodon on S3 — Silent Upload Failures (BucketOwnerEnforced/ACLs)
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- SELinux: Fixing Fail2ban grep execmem Denial
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- 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.socket Unreachable After Reboot (Tailscale Race Condition)
- Fail2ban & UFW Rule Bloat Cleanup
- Custom Fail2ban Jail: Apache Directory Scanning
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web_log_1m_successfulfor Redirect-Heavy WordPress Sites - Castopod: Stale Federated Avatar URLs After Remote Profile Updates
- Castopod Posts Don't Appear on Mastodon — Diagnosing the Federation Path
- Nextcloud AIO Unhealthy 20h After Nightly Update
- n8n Behind Reverse Proxy: X-Forwarded-For Trust Fix
- Docker & Caddy Recovery After Reboot (Fedora + SELinux)
- ISP SNI Filtering with Caddy
- Obsidian Vault Recovery — Loading Cache Hang
- Qwen2.5-14B OOM on RTX 3080 Ti (12GB)
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- Gemini CLI Manual Update
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- Gitea Actions Runner: Boot Race Condition Fix
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- Claude Desktop MCP Server Started via wsl.exe Sees Empty Environment (WSLENV)
- Claude Desktop MCP Mass-Disconnect After Blocking SSH Reboot
- Patching PHP 8.4 Implicit-Nullable Deprecations in Vendor Packages
- Ollama Drops Off Tailscale When Mac Sleeps
- Ollama:
ollama runwith Piped Stdin Bypasses Chat Template + SYSTEM Prompt - rsync over Tailscale: Hung in TCP Teardown After Transfer Completes
- iOS Tailscale Clients Report HostName="localhost" — Breaks /etc/hosts Generators
- macOS: Repeating Alert Tone from Mirrored iPhone Notification
- OBS Studio: Stale Script Paths After Windows Profile Rename
- ClamAV CPU Spike: Safe Scheduling with nice/ionice
- Logwatch Falsely Reports 'No freshclam updates' in ClamAV Daemon Mode
- Fedora CA Bundle Missing Symlink — TLS Breaks Fleet-Wide
- Netdata apps-group FD-utilisation false 100% (silenced fleet-wide)
- Ansible: Vault Password File Not Found
- Ansible: ansible.cfg Ignored on WSL2 Windows Mounts
- WSL2: PyTorch Training Deadlocks on Windows Filesystem Checkpoint Saves
- Ansible: SSH Timeout During dnf upgrade on Fedora Hosts
- Ansible: regex_search Capture-Group Argument Fails in set_fact
- Ansible: Ubuntu Reboot Detection Misses Kernel Upgrades
- Fedora Networking & Kernel Troubleshooting
- Systemd Session Scope Fails at Login
- wget/curl: URLs with Special Characters Fail in Bash
- Ansible: Check Mode False Positives in Verify/Assert Tasks
- Ansible Fails with Permission Denied While
ssh <alias>Works (Host Alias Bypass) - SSH Alias Falls Through to MagicDNS — Host-Key Verification Failure (No
HostBlock) - MagicDNS Names vs Pinned IPs for Tailscale SSH (After a Fleet Migration)
- Ghost EmailAnalytics Lag Warning — What It Means and When to Worry
- claude-mem: --setting-sources Empty Arg Bug (Claude Code 2.1.x)