我试图建立一个 EFK 堆栈。虽然 E+K 在默认命名空间中工作正常，但 Fluentd 容器无法连接到 elasticsearch。
kubectl get services -n default
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
elasticsearch-master ClusterIP 10.43.40.136 <none> 9200/TCP,9300/TCP 92m
elasticsearch-master-headless ClusterIP None <none> 9200/TCP,9300/TCP 92m
kibana-kibana ClusterIP 10.43.152.189 <none> 5601/TCP 74m
kubernetes ClusterIP 10.43.0.1 <none> 443/TCP 14d
我已经从这个 repo 安装了 fluentd 并将 url 更改为 elasticsearch
kubectl -n kube-system get pods | grep fluentd
fluentd-4fd2s 1/1 Running 0 51m
fluentd-7t2v5 1/1 Running 0 49m
fluentd-dfnfg 1/1 Running 0 50m
fluentd-lvrsv 1/1 Running 0 48m
fluentd-rv4td 1/1 Running 0 50m
但日志告诉我：
2021-07-23 21:38:59 +0000 [info]: starting fluentd-1.13.2 pid=7 ruby="2.6.8"
2021-07-23 21:38:59 +0000 [info]: spawn command to main: cmdline=["/usr/local/bin/ruby", "-Eascii-8bit:ascii-8bit", "/fluentd/vendor/bundle/ruby/2.6.0/bin/fluentd", "-c", "/fluentd/etc/fluent.conf", "-p", "/fluentd/plugins", "--gemfile", "/fluentd/Gemfile", "-r", "/fluentd/vendor/bundle/ruby/2.6.0/gems/fluent-plugin-elasticsearch-5.0.5/lib/fluent/plugin/elasticsearch_simple_sniffer.rb", "--under-supervisor"]
2021-07-23 21:39:01 +0000 [info]: adding match in @FLUENT_LOG pattern="fluent.**" type="null"
2021-07-23 21:39:01 +0000 [info]: adding filter pattern="kubernetes.**" type="kubernetes_metadata"
2021-07-23 21:39:01 +0000 [warn]: #0 [filter_kube_metadata] !! The environment variable 'K8S_NODE_NAME' is not set to the node name which can affect the API server and watch efficiency !!
2021-07-23 21:39:01 +0000 [info]: adding match pattern="**" type="elasticsearch"
2021-07-23 21:39:09 +0000 [warn]: #0 [out_es] Could not communicate to Elasticsearch, resetting connection and trying again. connect_write timeout reached
2021-07-23 21:39:09 +0000 [warn]: #0 [out_es] Remaining retry: 14. Retry to communicate after 2 second(s).
2021-07-23 21:39:18 +0000 [warn]: #0 [out_es] Could not communicate to Elasticsearch, resetting connection and trying again. connect_write timeout reached
2021-07-23 21:39:18 +0000 [warn]: #0 [out_es] Remaining retry: 13. Retry to communicate after 4 second(s).
2021-07-23 21:39:31 +0000 [warn]: #0 [out_es] Could not communicate to Elasticsearch, resetting connection and trying again. connect_write timeout reached
2021-07-23 21:39:31 +0000 [warn]: #0 [out_es] Remaining retry: 12. Retry to communicate after 8 second(s).
2021-07-23 21:39:52 +0000 [warn]: #0 [out_es] Could not communicate to Elasticsearch, resetting connection and trying again. connect_write timeout reached
2021-07-23 21:39:52 +0000 [warn]: #0 [out_es] Remaining retry: 11. Retry to communicate after 16 second(s).
2021-07-23 21:40:29 +0000 [warn]: #0 [out_es] Could not communicate to Elasticsearch, resetting connection and trying again. connect_write timeout reached
2021-07-23 21:40:29 +0000 [warn]: #0 [out_es] Remaining retry: 10. Retry to communicate after 32 second(s).
2021-07-23 21:41:38 +0000 [warn]: #0 [out_es] Could not communicate to Elasticsearch, resetting connection and trying again. connect_write timeout reached
我安装了 dig 并解决了该服务：
root@fluentd-dfnfg:/home/fluent# nslookup elasticsearch-master.default.svc.cluster.local
Server: 10.43.0.10
Address: 10.43.0.10#53
Name: elasticsearch-master.default.svc.cluster.local
Address: 10.43.40.136
我没有想法了。
PS：我使用的是加固的 RKE2。 (https://github.com/rancherfederal/rke2-ansible)