Elasitcsearch-ruby raises "Cannot get new connection from pool" error

2015-12-12 05:52:14 +0000 fluent.warn: {"next_retry":"2015-12-12 14:19:11
+0000","error_class":"Elasticsearch::Transport::Transport::Error","error":"Cannot
get new connection from
pool.","plugin_id":"object:3ffb5dfb2578","message":"temporarily failed to
flush the buffer. next_retry=2015-12-12 14:19:11 +0000
error_class="Elasticsearch::Transport::Transport::Error"
error="Cannot get new connection from pool
."
plugin_id="object:3ffb5dfb2578""}

(I upgrade to 1.2.0) BUT I am using, AWS elastic search service.

aws-sdk-v1 (1.64.0)

elasticsearch (1.0.14)
elasticsearch-api (1.0.14)
elasticsearch-transport (1.0.14)

fluent-logger (0.4.10)
fluent-mixin-config-placeholders (0.3.0)
fluent-mixin-plaintextformatter (0.2.6)
fluent-mixin-rewrite-tag-name (0.1.0)
fluent-plugin-elasticsearch (1.2.0)
fluent-plugin-geoip (0.5.1)
fluent-plugin-mongo (0.7.10)
fluent-plugin-rewrite-tag-filter (1.4.1)
fluent-plugin-s3 (0.5.9)
fluent-plugin-scribe (0.10.14)
fluent-plugin-script (0.0.2)
fluent-plugin-td (0.10.27)
fluent-plugin-td-monitoring (0.2.1)
fluent-plugin-webhdfs (0.4.1)

*I think that is a AWS issue, * that returns a different JSON for the same
API, (no address data) as you said before. It's a pity... because if they
change the standard behavior, a lot of plugins are not going to work.