diff --git a/scripts/backup.sh b/scripts/backup.sh
index a7de7ab..1d91bd9 100755
--- a/scripts/backup.sh
+++ b/scripts/backup.sh
@@ -61,7 +61,7 @@ run_and_notify() {
 echo "=== Backup started $(date) ===" | tee -a "$LOG"
 
 # Synology: attempt only if reachable (SSH key auth, 30s timeout for HDD spin-up)
-if ssh -o ConnectTimeout=30 -o BatchMode=yes synology true 2>/dev/null; then
+if ssh -o ConnectTimeout=30 -o BatchMode=yes synology 'ls /volume1/backup > /dev/null 2>&1' 2>/dev/null; then
   run_and_notify "sftp:${SYNOLOGY_HOST}:${SYNOLOGY_PATH}" "Synology" "desktop" "synology"
 else
   echo "Synology unreachable — skipping SFTP backup" | tee -a "$LOG"