fix #844: document first VM/CT start-up delay

adds subsection to the "PVE Node Management" section, discussing the
initial VM/CT startup delay feature.

also makes reference to this in the Qemu & LXC sections of the
documentation.

Signed-off-by: Dylan Whyte <d.whyte@proxmox.com>

pct.adoc

@@ -433,6 +433,11 @@ always start after those where the parameter is set, and this parameter only
 makes sense between the machines running locally on a host, and not
 cluster-wide.
 
+If you require a delay between the host boot and the booting of the first
+container, see the section on
+xref:first_guest_boot_delay[Proxmox VE Node Management].
+
+
 Hookscripts
 ~~~~~~~~~~~
 

pvenode.adoc

@@ -83,6 +83,24 @@ of `<node>` obtained from the `wakeonlan` property. The node specific
 pvenode config set -wakeonlan XX:XX:XX:XX:XX:XX
 ----
 
+
+[[first_guest_boot_delay]]
+First Guest Boot Delay
+~~~~~~~~~~~~~~~~~~~~~~
+
+In case your VMs/containers rely on slow-to-start external resources, for
+example an NFS server, you can also set a per-node delay between the time {pve}
+boots and the time the first VM/container that is configured to autostart boots
+(see xref:qm_startup_and_shutdown[Automatic Start and Shutdown of Virtual Machines]).
+
+You can achieve this by setting the following (where `10` represents the delay
+in seconds):
+
+----
+pvenode config set --startall-onboot-delay 10
+----
+
+
 // TODO: extend and improve chapter!
 
 ifdef::manvolnum[]

qm.adoc

@@ -923,6 +923,9 @@ start after those where the parameter is set. Further, this parameter can only
 be enforced between virtual machines running on the same host, not
 cluster-wide.
 
+If you require a delay between the host boot and the booting of the first VM,
+see the section on xref:first_guest_boot_delay[Proxmox VE Node Management].
+
 
 [[qm_qemu_agent]]
 Qemu Guest Agent