diff --git a/docs/runbooks/esh-pve-cluster-pve9-upgrade-plan.md b/docs/runbooks/esh-pve-cluster-pve9-upgrade-plan.md
index e2f13f7..cc59642 100644
--- a/docs/runbooks/esh-pve-cluster-pve9-upgrade-plan.md
+++ b/docs/runbooks/esh-pve-cluster-pve9-upgrade-plan.md
@@ -63,6 +63,10 @@ one-off backups of 103-107 to pbs-ana (1530-1532); pve8to9 0 FAIL. Then:
   dockerd did not restart it. zigbee2mqtt restart-looped without its broker until mosquitto was started by hand
   (`compose up -d`, 15:45). **After any VM 100 reboot, check mosquitto and zigbee2mqtt.**
 - Total ESH impact: DNS ~6 min (15:33-15:39); DB ~12 min; Zigbee ~13 min; NAS/media ~4 min.
+- **Better for the real esh-nas-pve reboot: do NOT shut VM 100 down. That is what took ESH DNS out.** Only two of its containers use
+  the NAS shares: `calibre-web-automated` (/mnt/books) and `beszel-agent` (stats of /mnt/books and /mnt/backup). Stop those two,
+  `umount /mnt/books /mnt/backup` inside VM 100, reboot the NAS host, then remount and start them. DNS, Z2M/mosquitto and the rest
+  stay up. VM 101 still has to shut down (its disk is qcow2 on the `esh-nas` NFS storage).
 
 ## Pre-flight (no guest downtime)