First version of the resolvectl munin plugin (#1450)

* First version of the resolvectl munin plugin

* Fixed autoconf check

---------

Co-authored-by: Scott Hollenbeck <sah@hollenmail.com>

plugins/resolvectl/resolvectl

@@ -0,0 +1,123 @@
+#!/bin/sh
+# -*- sh -*-
+
+set -e
+
+: << =cut
+
+=head1 NAME
+
+resolvectl - Plugin to monitor resolvectl statistics.
+
+=head1 APPLICABLE SYSTEMS
+
+Any server running systemd-resolved
+
+=head1 CONFIGURATION
+
+[resolvectl]
+user root
+
+=head1 NOTES
+
+Uses the command "resolvectl statistics"
+
+=head1 AUTHOR
+
+Scott Hollenbeck <sah6284@gmail.com>
+
+=head1 LICENSE
+
+GPLv2
+
+=head1 VERSION
+
+1.0
+
+=head1 MAGIC MARKERS
+
+ #%# family=auto
+ #%# capabilities=autoconf
+
+=cut
+
+. "$MUNIN_LIBDIR/plugins/plugin.sh"
+
+if [ "$1" = "autoconf" ]; then
+    resolvectl statistics >/dev/null 2>&1
+    ret=$?
+    if [ "$ret" -eq 0 ]; then
+        echo yes
+        exit 0
+    else
+        if [ "$ret" -eq 1 ]; then
+            echo "no (could not run \"resolvectl\")"
+            exit 0
+        else
+            echo "no (unknown resolvectl return value "$ret")"
+            exit 0
+        fi
+    fi
+fi
+
+if [ "$1" = "config" ]; then
+
+    echo 'graph_title resolvectl statistics'
+    echo 'graph_args --base 1000 -l 0'
+    echo 'graph_vlabel count'
+    echo 'graph_category dns'
+    echo 'current-transactions.label current transactions'
+    echo 'current-transactions.type DERIVE'
+    echo 'current-transactions.min 0'
+    echo 'total-transactions.label total transactions'
+    echo 'total-transactions.type DERIVE'
+    echo 'total-transactions.min 0'
+    echo 'cache-size.label cache size'
+    echo 'cache-size.type DERIVE'
+    echo 'cache-size.min 0'
+    echo 'cache-hits.label cache hits'
+    echo 'cache-hits.type DERIVE'
+    echo 'cache-hits.min 0'
+    echo 'cache-misses.label cache misses'
+    echo 'cache-misses.type DERIVE'
+    echo 'cache-misses.min 0'
+    echo 'total-timeouts.label total timeouts'
+    echo 'total-timeouts.type DERIVE'
+    echo 'total-timeouts.min 0'
+    echo 'total-timeouts-stale.label total timeouts stale'
+    echo 'total-timeouts-stale.type DERIVE'
+    echo 'total-timeouts-stale.min 0'
+    echo 'total-failures.label total failures'
+    echo 'total-failures.type DERIVE'
+    echo 'total-failures.min 0'
+    echo 'total-failures-stale.label total failures stale'
+    echo 'total-failures-stale.type DERIVE'
+    echo 'total-failures-stale.min 0'
+    echo 'dnssec-secure.label dnssec secure'
+    echo 'dnssec-secure.type DERIVE'
+    echo 'dnssec-secure.min 0'
+    echo 'dnssec-insecure.label dnssec insecure'
+    echo 'dnssec-insecure.type DERIVE'
+    echo 'dnssec-insecure.min 0'
+    echo 'dnssec-bogus.label dnssec bogus'
+    echo 'dnssec-bogus.type DERIVE'
+    echo 'dnssec-bogus.min 0'
+    echo 'dnssec-indeterminate.label dnssec indeterminate'
+    echo 'dnssec-indeterminate.type DERIVE'
+    echo 'dnssec-indeterminate.min 0'
+    exit 0
+fi
+
+resolvectl statistics | awk '/Current Transactions/{print "current-transactions.value " $NF};\
+/Total Transactions/{print "total-transactions.value " $NF};\
+/Current Cache Size/{print "cache-size.value " $NF};\
+/Cache Hits/{print "cache-hits.value " $NF};\
+/Cache Misses/{print "cache-misses.value " $NF};\
+/Total Timeouts:/{print "total-timeouts.value " $NF};\
+/Total Timeouts \(Stale Data Served/{print "total-timeouts-stale.value " $NF};\
+/Total Failure Responses:/{print "total-failures.value " $NF};\
+/Total Failure Responses \(Stale Data Served/{print "total-failures-stale.value " $NF};\
+/Secure/{print "dnssec-secure.value " $NF};\
+/Insecure/{print "dnssec-insecure.value " $NF};\
+/Bogus/{print "dnssec-bogus.value " $NF};\
+/Indeterminate/{print "dnssec-indeterminate.value " $NF};'