README
¶
prometheus
prometheus enables Prometheus metrics.
The default location for the metrics is localhost:9153
. The metrics path is fixed to /metrics
.
The following metrics are exported:
coredns_dns_request_count_total{zone, proto, family}
- total query count.coredns_dns_request_duration_seconds{zone}
- duration to process each query.coredns_dns_request_size_bytes{zone, proto}
- size of the request in bytes.coredns_dns_request_do_count_total{zone}
- queries that have the DO bit setcoredns_dns_request_type_count_total{zone, type}
- counter of queries per zone and type.coredns_dns_response_size_bytes{zone, proto}
- response size in bytes.coredns_dns_response_rcode_count_total{zone, rcode}
- response per zone and rcode.
Each counter has a label zone
which is the zonename used for the request/response.
Extra labels used are:
proto
which holds the transport of the response ("udp" or "tcp")- The address family (
family
) of the transport (1 = IP (IP version 4), 2 = IP6 (IP version 6)). type
which holds the query type. It holds most common types (A, AAAA, MX, SOA, CNAME, PTR, TXT, NS, SRV, DS, DNSKEY, RRSIG, NSEC, NSEC3, IXFR, AXFR and ANY) and "other" which lumps together all other types.- The
response_rcode_count_total
has an extra labelrcode
which holds the rcode of the response.
If monitoring is enabled, queries that do not enter the plugin chain are exported under the fake name "dropped" (without a closing dot - this is never a valid domain name).
Syntax
prometheus [ADDRESS]
For each zone that you want to see metrics for.
It optionally takes an address to which the metrics are exported; the default
is localhost:9153
. The metrics path is fixed to /metrics
.
Examples
Use an alternative address:
. {
prometheus localhost:9253
}
Or via an enviroment variable (this is supported throughout the Corefile): export PORT=9253
, and
then:
. {
prometheus localhost:{$PORT}
}
Bugs
When reloading, we keep the handler running, meaning that any changes to the handler's address aren't picked up. You'll need to restart CoreDNS for that to happen.
Documentation
¶
Overview ¶
Package metrics implement a handler and plugin that provides Prometheus metrics.
Index ¶
- Variables
- type Metrics
- func (m *Metrics) AddZone(z string)
- func (m *Metrics) Name() string
- func (m *Metrics) OnShutdown() error
- func (m *Metrics) OnStartup() error
- func (m *Metrics) RemoveZone(z string)
- func (m *Metrics) ServeDNS(ctx context.Context, w dns.ResponseWriter, r *dns.Msg) (int, error)
- func (m *Metrics) ZoneNames() []string
Constants ¶
This section is empty.
Variables ¶
var ListenAddr string
ListenAddr is assigned the address of the prometheus listener. Its use is mainly in tests where we listen on "localhost:0" and need to retrieve the actual address.
Functions ¶
This section is empty.
Types ¶
type Metrics ¶
Metrics holds the prometheus configuration. The metrics' path is fixed to be /metrics
func (*Metrics) OnShutdown ¶
OnShutdown tears down the metrics on shutdown and restart.
func (*Metrics) RemoveZone ¶
RemoveZone remove zone z from m.