stats

stats - statistics plugin for CoreDNS

stats is a CoreDNS plugin which can be used to store request statics into a database backend. The plugin is designed to be used with a SQL database backend, but can be extended to support other databases as well.

Currently the plugin supports PostgreSQL.

Usage

CoreDNS Binary

You can include stats in your CoreDNS just as you would include any other CoreDNS plugin.

# Clone coredns to a local location
$ git clone git@github.com:coredns/coredns.git ~/dns-server/coredns

# Clone stats plugin to a close location
$ git clone git@github.com:GustavoKatel/stats.git ~/dns-server/stats

# Symlink stats location into coredns/plugin/stats
$ cd ~/dns-server/coredns/plugin
$ ln -s ../stats ./stats

# Update plugin.cfg and put the line "stats:stats" before the "forward:forward" line

# Build CoreDNS
$ cd ~/dns-server/coredns
$ go generate
$ make
$ ./coredns -conf Corefile

Corefile

The stats directive inside Corefile requires one argument, which is the connection string of the backend. The connection string should be in the format of driver://user:password@host:port/database.

Optionally, you can specify a block with the following options:

• workers [integer] The number of workers to use for processing the requests. The default value is 3.
• queryTimeout [Go duration] The timeout for the database queries. The default value is 5 seconds.
• statsPrefix [string] The prefix to be used for the statistics table. The default value is coredns.

stats postgresql://user:pass@postgres.postgres.svc.cluster.local:5432/coredns

Or

stats postgresql://user:pass@postgres.postgres.svc.cluster.local:5432/coredns {
    workers 3
    queryTimeout 5s
    statsPrefix coredns
}

This is a sample Corefile including the stats directive. It will store statistics in a PostgreSQL database and forward the requests to Cloudflare DNS.

.:53 {
    metadata
    prometheus 0.0.0.0:9153

    bind 0.0.0.0

    stats postgresql://user:pass@postgres.postgres.svc.cluster.local:5432/coredns {
        workers 3
        queryTimeout 5s
        statsPrefix coredns
    }

    forward . tls://1.1.1.1 tls://1.0.0.1 {
        tls_servername cloudflare-dns.com
    }
    log
    errors
}

plugin.cfg

This is a sample middleware configuration file. The order of plugins here is important. This is the order in which plugins will be executed for incoming requests.

metadata:metadata prometheus:metrics log:log forward:forward stats:stats

Interaction with Other CoreDNS Plugins

metadata

The plugin will store all metadata stored by the metadata plugin for each request. The metadata will be stored in a JSON format.