SearchVarnish Enterprise
The rtstatus vmod allows you to query your Varnish server for a JSON object containing
counters.
Visiting the URL /rtstatus.json on the Varnish server will produce an
application/json response of the following format:
{
"uptime" : "0+16:12:58",
"uptime_sec": 58378.00,
"hitrate": 30.93,
"load": 2.73,
"varnish_version" : "[...]",
"server_id": "[...]",
"be_info":
[
{ "server_name": "[...]", "happy": [...], "bereq_tot": [...], [...] },
[...]
]
"[counter]": {"type": "[...]", "ident": "[...]", "descr": "[...]", "value": [...] },
[...]
}
It comes with a user interface in the form of a static web page that renders
the JSON file at the URL /rtstatus.html.
Varnish version Varnish version installed on your server.
Varnish uptime Child uptime.
Hit ratio Absolute hitrate ratio. It is evaluated as: (n_hit) / (n_hit + n_miss). Note that uptime is not taken into consideration for this counter.
Avg hitrate Average hitrate since uptime. It is evaluated as: ((n_hit) / (n_hit + n_miss)) / uptime.
Avg load Average load since uptime. It is evaluated as: n_requests / uptime.
The list of counters is described in the varnish-counters(7) manual, and
for convenience backend counters are grouped by backend in the be_info
field.
In your VCL you can use this vmod along the following lines:
vcl 4.0;
import rtstatus;
sub vcl_recv {
if (req.url == "/rtstatus.json" || req.url == "/rtstatus.html") {
return (synth(200));
}
}
sub vcl_synth {
if (req.url == "/rtstatus.json") {
rtstatus.synthetic_json();
return (deliver);
}
if (req.url == "/rtstatus.html") {
rtstatus.synthetic_html();
return (deliver);
}
}
VOID synthetic_json()
Returns a JSON object with relevant Varnish counters. Takes care of setting the content type.
Arguments: None
Type: Function
Returns: None
Restricted to: vcl_synth, vcl_backend_error
VOID synthetic_html()
Renders in a UI the JSON file obtained from the synthetic_json function. Takes care of setting the content type.
Arguments: None
Type: Function
Returns: None
Restricted to: vcl_synth, vcl_backend_error
The rtstatus VMOD is available in Varnish Enterprise version 6.0.0r0 and later.