add external metric server to sysadmin.adoc

this did only exist as a wiki article, but
since we ship with it, this should be in the
reference documentation

Signed-off-by: Dominik Csapak <d.csapak@proxmox.com>

pve-external-metric-server.adoc

@@ -0,0 +1,57 @@
+External Metric Server
+----------------------
+include::attributes.txt[]
+ifdef::wiki[]
+:pve-toplevel:
+endif::wiki[]
+
+Starting with {pve} 4.0, you can define external metric servers,
+which will be sent various stats about your hosts, virtual machines and storages.
+
+Currently supported are:
+
+ * graphite (see http://graphiteapp.org )
+ * influxdb (see https://www.influxdata.com/time-series-platform/influxdb/ )
+
+The server definitions are saved in
+ /etc/pve/status.cfg
+
+Graphite server configuration
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+The definition of a server is:
+
+ graphite:
+    server your-server
+    port your-port
+    path your-path
+
+where your-port defaults to *2003*
+and your-path defaults to *proxmox*
+
+{pve} sends the data over udp, so the graphite server
+has to be configured for this
+
+Influxdb plugin configuration
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+The definition is:
+
+ influxdb:
+    server your-server
+    port your-port
+
+{pve} sends the data over udp, so the influxdb server
+has to be configured for this
+
+Here is an example configuration for influxdb (on your influxdb server):
+
+ [[udp]]
+   enabled = true
+   bind-address = "0.0.0.0:8089"
+   database = "proxmox"
+   batch-size = 1000
+   batch-timeout = "1s"
+
+With this configuration, your server listens on all IP adresses on
+port 8089, and writes the data in the *proxmox* database

sysadmin.adoc

@@ -43,6 +43,8 @@ See Also
 
 * link:/wiki/System_Software_Updates[System Software Updates]
 
+* link:/wiki/External_Metric_Server[External Metric Server]
+
 * link:/wiki/Disk_Health_Monitoring[Disk Health Monitoring]
 
 * link:/wiki/Logical_Volume_Manager_(LVM)[Logical Volume Manager (LVM)]
@@ -62,6 +64,8 @@ include::pve-network.adoc[]
 
 include::system-timesync.adoc[]
 
+include::pve-external-metric-server.adoc[]
+
 include::pve-disk-health-monitoring.adoc[]
 
 include::local-lvm.adoc[]