From 8cc1b61d20ad521faf7ffe1cd4670685374c9c0e Mon Sep 17 00:00:00 2001
From: Florian Forster <octo@collectd.org>
Date: Mon, 28 Nov 2016 11:02:53 +0100
Subject: [PATCH] write_tsdb plugin: Rename options to
 "Resolve{Interval,Jitter}".

---
 src/collectd.conf.pod | 33 +++++++++++++++++----------------
 src/write_tsdb.c      |  4 ++--
 2 files changed, 19 insertions(+), 18 deletions(-)

diff --git a/src/collectd.conf.pod b/src/collectd.conf.pod
index fce59032..b043a89f 100644
--- a/src/collectd.conf.pod
+++ b/src/collectd.conf.pod
@@ -8143,8 +8143,8 @@ packets.
 Synopsis:
 
  <Plugin write_tsdb>
-   DNS_Cache_TTL 60
-   DNS_Random_Cache_TTL 60
+   ResolveInterval 60
+   ResolveJitter 60
    <Node "example">
      Host "tsd-1.my.domain"
      Port "4242"
@@ -8159,24 +8159,25 @@ Global directives are:
 
 =over 4
 
-=item B<DNS_Cache_TTL> I<ttl>
+=item B<ResolveInterval> I<seconds>
 
-=item B<DNS_Random_Cache_TTL> I<ttl>
+=item B<ResolveJitter> I<seconds>
 
-When Collectd connects to a TSDB node, it will request the DNS. This can become
-a problem is the TSDN node is unavailable or badly configured because Collected
-will request DNS in order to reconnect for every metric, which can flood your DNS.
-So you can cache the last value for C<ttl> seconds (default: 600s e.g; 10 min).
+When I<collectd> connects to a TSDB node, it will request the DNS. This can
+become a problem if the TSDN node is unavailable or badly configured because
+collectd will request DNS in order to reconnect for every metric, which can
+flood your DNS. So you can cache the last value for I<ResolveInterval> seconds
+(default: B<600>, i.e. 10 minutes).
 
-You can also define a random ttl. This prevents all your Collectd servers to
-request the DNS at the same time when the connection fails. Default value is
-15 * the write_tsdb interval (or the global interval if write_tsdb interval is not
-defined).
+You can also define a jitter, a random interval to wait in addition to
+I<ResolveInterval>. This prevents all your collectd servers to resolve the
+hostname at the same time when the connection fails. Default value is 15 * the
+interval of the I<write_tsdb plugin> (defaults to 10 seconds).
 
-Note : if the DNS resolution has already been successful, if the socket closes,
-the plugin will try to reconnect as soon as possible with the cached information.
-DNS is queried only when the socket is closed for a long time (DNS_Cache_TTL + 
-DNS_Random_Cache_TTL)
+B<Note:> If the DNS resolution has already been successful when the socket
+closes, the plugin will try to reconnect immediately with the cached
+information. DNS is queried only when the socket is closed for a longer than
+I<ResolveInterval> + I<ResolveJitter> seconds.
 
 =back
 
diff --git a/src/write_tsdb.c b/src/write_tsdb.c
index 49a3b414..6d8fe60c 100644
--- a/src/write_tsdb.c
+++ b/src/write_tsdb.c
@@ -645,9 +645,9 @@ static int wt_config(oconfig_item_t *ci) {
 
     if (strcasecmp("Node", child->key) == 0)
       wt_config_tsd(child);
-    else if (strcasecmp("DNS_Cache_TTL", child->key) == 0)
+    else if (strcasecmp("ResolveInterval", child->key) == 0)
       cf_util_get_cdtime(child, &dnsttl);
-    else if (strcasecmp("DNS_Random_Cache_TTL", child->key) == 0) {
+    else if (strcasecmp("ResolveJitter", child->key) == 0) {
       config_random_ttl = 1;
       cf_util_get_cdtime(child, &dnsrandomttl);
     } else {
-- 
2.11.0