home-server/macos/Jellyfin-SMB.md

Jellyfin + macOS: Persistent NFS Mount (Fix for Libraries Randomly “Clearing”)

This README documents the working fix I applied when Jellyfin (on a Mac mini) periodically “lost” or cleared my Movies/TV libraries that live on a NAS mounted over NFS.

It includes the exact commands, files, and rationale so I can reproduce it later.

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Problem Summary

• Symptom: Every day or two, Jellyfin showed empty Movies/TV libraries.
• Media location: NFS share at /Volumes/media from NAS 192.168.50.105:/media.
• Root cause: macOS was using autofs (/- /etc/auto_nfs). autofs can unmount after inactivity or brief network blips. When the mount disappears during a Jellyfin scan/file-watch, Jellyfin sees files as missing and removes them from its DB.

Solution Summary

• Stop using autofs for this path.
• Create a persistent mount at boot using a LaunchDaemon and a small network‑aware mount script.
• The script:
  • Is idempotent: does nothing if already mounted.
  • Checks NAS reachability first.
  • Logs to /var/log/mount_media.(out|err).
  • Optionally restarts Jellyfin (Homebrew service) if the mount comes back.

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Prerequisites / Assumptions

• macOS with admin (sudo) access.
• NFS server: 192.168.50.105 exporting /media (adjust as needed).
• Mount point: /Volumes/media (adjust as needed).
• Jellyfin installed (optional Homebrew service restart in script).

Tip: If your NAS requires privileged source ports for NFSv4, resvport helps. The script falls back to noresvport if needed.

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Steps (copy/paste commands)

1) Disable autofs for this path and unmount any automounted share

# Backup and comment out the direct map for NFS
sudo cp /etc/auto_master /etc/auto_master.bak.$(date +%F_%H%M%S)
sudo sed -i.bak 's|^/- /etc/auto_nfs|#/- /etc/auto_nfs|' /etc/auto_master

# Reload automountd (will unmount /Volumes/media if it was automounted)
sudo automount -vc

# Ensure the mountpoint is not currently mounted (ignore errors if already unmounted)
sudo umount /Volumes/media 2>/dev/null || sudo umount -f /Volumes/media 2>/dev/null || true

Note: If chown/chmod say “Operation not permitted,” the path is still mounted (or your NAS has root-squash). Unmount first.

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2) Create the network‑aware mount script

sudo mkdir -p /usr/local/sbin

sudo tee /usr/local/sbin/mount_media_nfs.sh > /dev/null <<'SH'
#!/bin/sh
set -eu

LOG="/var/log/mount_media.out"
ERR="/var/log/mount_media.err"
MOUNT="/Volumes/media"

# SMB server settings — use domain name (FQDN)
HOST="nas.example.local"   # <- change to your domain
SHARE="media"              # <- change share name if needed

# Optional auth:
# - If SMB_USER is set, script will try authenticated mount.
# - Supply SMB_PASS (environment) OR set SMB_KEYCHAIN_ITEM to fetch password from Keychain.
SMB_USER="${SMB_USER:-}"
SMB_PASS="${SMB_PASS:-}"
SMB_KEYCHAIN_ITEM="${SMB_KEYCHAIN_ITEM:-}"

# Ensure mountpoint exists
[ -d "$MOUNT" ] || mkdir -p "$MOUNT"

# If already mounted on the mountpoint, exit quietly
if mount | awk '{print $3}' | grep -qx "$MOUNT"; then
  echo "$(date) already mounted: $MOUNT" >>"$LOG"
  exit 0
fi

# Preflight: only try to mount when SMB port is reachable (try 445 then 139)
if ! ( /usr/bin/nc -G 2 -z "$HOST" 445 >/dev/null 2>&1 || /usr/bin/nc -G 2 -z "$HOST" 139 >/dev/null 2>&1 ); then
  echo "$(date) NAS not reachable on SMB ports (445/139), skipping mount" >>"$LOG"
  exit 0
fi

# Helpful server listing for debugging (doesn't include credentials)
echo "$(date) smbutil listing for debugging" >>"$LOG" 2>>"$ERR"
smbutil view "//$HOST" >>"$LOG" 2>>"$ERR" || true
smbutil view "//guest@$HOST" >>"$LOG" 2>>"$ERR" || true

# Helper: function to verify mount and restart Jellyfin if needed
verify_and_exit() {
  if mount | awk '{print $3}' | grep -qx "$MOUNT"; then
    echo "$(date) mount OK: $MOUNT" >>"$LOG"
    if command -v brew >/dev/null 2>&1 && brew services list | grep -q '^jellyfin\b'; then
      echo "$(date) restarting Jellyfin (brew services)" >>"$LOG"
      brew services restart jellyfin >>"$LOG" 2>>"$ERR" || true
    fi
    exit 0
  fi
}

# Try authenticated mount if SMB_USER provided
if [ -n "$SMB_USER" ]; then
  # Retrieve password from Keychain if requested and SMB_PASS not set
  if [ -z "$SMB_PASS" ] && [ -n "$SMB_KEYCHAIN_ITEM" ]; then
    # Try to read password from Keychain (service name = SMB_KEYCHAIN_ITEM, account = SMB_USER)
    # The -w flag prints only the password
    SMB_PASS="$(security find-generic-password -s "$SMB_KEYCHAIN_ITEM" -a "$SMB_USER" -w 2>/dev/null || true)"
  fi

  if [ -n "$SMB_PASS" ]; then
    # Use password via stdin to avoid exposing it in process list
    echo "$(date) attempting authenticated mount as user '$SMB_USER' -> $MOUNT" >>"$LOG"
    # Do NOT include the password in the URL or logs.
    MOUNT_URL="//${SMB_USER}@${HOST}/${SHARE}"
    # Send password followed by newline to mount_smbfs which will read it from stdin
    if printf '%s\n' "$SMB_PASS" | /sbin/mount_smbfs "$MOUNT_URL" "$MOUNT" >>"$LOG" 2>>"$ERR"; then
      verify_and_exit
    else
      echo "$(date) authenticated mount attempt FAILED" >>"$ERR"
      # Fall through to guest attempts
    fi
  else
    # No password available for authenticated mount
    echo "$(date) SMB_USER set but no SMB_PASS or Keychain entry found -> will try guest" >>"$LOG"
  fi
fi

# If we reach here, try guest access (null/anonymous session)
echo "$(date) trying guest/null session (mount_smbfs -N) -> $MOUNT" >>"$LOG"
if /sbin/mount_smbfs -N "//$HOST/$SHARE" "$MOUNT" >>"$LOG" 2>>"$ERR"; then
  verify_and_exit
fi

echo "$(date) trying explicit guest user (guest@$HOST) -> $MOUNT" >>"$LOG"
if /sbin/mount_smbfs "//guest@$HOST/$SHARE" "$MOUNT" >>"$LOG" 2>>"$ERR"; then
  verify_and_exit
fi

# If we reached here, all attempts failed
echo "$(date) ALL SMB mount attempts FAILED" >>"$ERR"
echo "------ smbutil status ------" >>"$ERR"
smbutil statshares -a >>"$ERR" 2>&1 || true
echo "------ mount table ------" >>"$ERR"
mount >>"$ERR" 2>&1 || true

exit 1
SH

sudo chmod 755 /usr/local/sbin/mount_media_smb.sh

---

3) Create the LaunchDaemon (mount at boot, re-check periodically, network‑aware)

sudo tee /Library/LaunchDaemons/com.local.mountmedia.plist > /dev/null <<'PLIST'
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
  <key>Label</key>
  <string>com.local.mountmedia</string>
  <key>ProgramArguments</key>
  <array>
    <string>/usr/local/sbin/mount_media_smb.sh</string>
  </array>
  <key>RunAtLoad</key>
  <true/>
  <key>StartInterval</key>
  <integer>300</integer>
  <key>KeepAlive</key>
  <dict>
    <key>NetworkState</key>
    <true/>
  </dict>
  <key>StandardOutPath</key>
  <string>/var/log/mount_media.out</string>
  <key>StandardErrorPath</key>
  <string>/var/log/mount_media.err</string>
</dict>
</plist>
PLIST

sudo chown root:wheel /Library/LaunchDaemons/com.local.mountmedia.plist
sudo chmod 644 /Library/LaunchDaemons/com.local.mountmedia.plist
sudo plutil -lint /Library/LaunchDaemons/com.local.mountmedia.plist

sudo launchctl bootout system /Library/LaunchDaemons/com.local.mountmedia.plist 2>/dev/null || true
sudo launchctl bootstrap system /Library/LaunchDaemons/com.local.mountmedia.plist
sudo launchctl enable system/com.local.mountmedia
sudo launchctl kickstart -k system/com.local.mountmedia

---

4) Run once and verify

# Run once now (idempotent; logs "already mounted" if present)
sudo /usr/local/sbin/mount_media_smb.sh

# LaunchDaemon status
sudo launchctl print system/com.local.mountmedia | egrep 'state|last exit|PID' || true

# Mount status (should NOT say "automounted")
mount | grep " on /Volumes/media "

# SMB mount parameters
smbstat -m | sed -n '/\/Volumes\/media/,+12p'

# Script logs
tail -n 100 /var/log/mount_media.out /var/log/mount_media.err 2>/dev/null || true

---

5) Jellyfin settings

• Temporarily disable “Enable real-time monitoring” for libraries under /Volumes/media until you confirm the mount stays stable.
• Then run “Scan Library Files” to repopulate anything previously removed.

---

6) Reboot test (recommended)

sudo shutdown -r now

After reboot:

mount | grep " on /Volumes/media " || echo "Not mounted yet"
sudo launchctl print system/com.local.mountmedia | egrep 'state|last exit' || true
tail -n 100 /var/log/mount_media.out /var/log/mount_media.err 2>/dev/null || true

---

Rationale for Key Choices

• Persistent mount (LaunchDaemon) instead of autofs:
  • autofs can unmount after inactivity; Jellyfin then removes items it thinks are gone.
  • LaunchDaemon ensures the mount is present before scans and remains mounted.
• smb options:
  • hard: Blocks I/O until server responds, avoiding spurious “file missing” errors.
  • nfsvers=4.0: Matches typical NAS defaults and the client’s chosen version.
  • resvport then fallback noresvport: Some servers require privileged ports; the script tries both.
• Network preflight:
  • Check TCP/2049 reachability to avoid “Network is unreachable” failures (exit code 51) at boot or during link flaps.
• Logging:
  • /var/log/mount_media.out and .err make it easy to correlate with Jellyfin logs.

---

Troubleshooting

• “Operation not permitted” when chown/chmod:
  • The path is mounted over NFS, and root-squash likely prevents ownership changes from the client. Unmount first or change ownership on the NAS.
• LaunchDaemon errors:
  • Validate plist: sudo plutil -lint /Library/LaunchDaemons/com.local.mountmedia.plist
  • Service state: sudo launchctl print system/com.local.mountmedia
• Mount health:
  • nfsstat -m should show vers=4.0, hard, resvport/noresvport.
• Network/power:
  • Prevent system sleep that drops the NIC; enable “Wake for network access.”

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Optional: If you must keep autofs

Increase the autofs timeout so it doesn’t unmount on brief inactivity (less ideal than the LaunchDaemon approach):

sudo cp /etc/auto_master /etc/auto_master.bak.$(date +%F_%H%M%S)
sudo sed -i.bak -E 's|^/-[[:space:]]+/etc/auto_nfs$|/- -timeout=604800 /etc/auto_nfs|' /etc/auto_master
sudo automount -vc

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Reverting

To revert to autofs:

# Stop and remove LaunchDaemon
sudo launchctl bootout system /Library/LaunchDaemons/com.local.mountmedia.plist
sudo rm -f /Library/LaunchDaemons/com.local.mountmedia.plist

# Restore /etc/auto_master (uncomment direct map) and reload
sudo sed -i.bak 's|^#/- /etc/auto_nfs|/- /etc/auto_nfs|' /etc/auto_master
sudo automount -vc

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Notes

• Change permissions/ownership on the NFS export from the NAS, not the macOS client (root-squash).
• showmount may fail against NFSv4-only servers; it’s not needed here.
• Adjust SERVER, MOUNT, and StartInterval to suit your environment.