【Rocket.Chat】MongoDBの再起動後にMongoTimeoutErrorとなる事象メモ

事象

RocketchatサーバとMongoDBの接続がMongoTimeoutErrorとなって利用できない。

Got exception while polling query MongoTimeoutError: Server selection timed out after 10000 ms
    at Timeout._onTimeout (/app/bundle/programs/server/npm/node_modules/meteor/npm-mongo/node_modules/mongodb-core/lib/sdam/topology.js:773:16)
    at listOnTimeout (internal/timers.js:549:17)
    at processTimers (internal/timers.js:492:7)
 => awaited here:
    at Function.Promise.await (/app/bundle/programs/server/npm/node_modules/meteor/promise/node_modules/meteor-promise/promise_server.js:56:12)
    at packages/mongo/mongo_driver.js:1037:14
    at /app/bundle/programs/server/npm/node_modules/meteor/promise/node_modules/meteor-promise/fiber_pool.js:43:40
 => awaited here:
    at Promise.await (/app/bundle/programs/server/npm/node_modules/meteor/promise/node_modules/meteor-promise/promise_server.js:60:12)
    at SynchronousCursor._nextObject (packages/mongo/mongo_driver.js:1086:38)
    at SynchronousCursor.forEach (packages/mongo/mongo_driver.js:1100:22)
    at Cursor.<computed> [as forEach] (packages/mongo/mongo_driver.js:882:44)
    at OplogObserveDriver._runQuery (packages/mongo/oplog_observe_driver.js:729:16)
    at packages/mongo/oplog_observe_driver.js:699:14
    at Meteor.EnvironmentVariable.EVp.withValue (packages/meteor.js:1234:12)
    at packages/meteor.js:550:25
    at runWithEnvironment (packages/meteor.js:1286:24) {
  name: 'MongoTimeoutError',
  [Symbol(mongoErrorContextSymbol)]: {}
}

環境情報

• Rocket.Chat Version: 3.2.2
• MongoDB Version: 4.0.18

原因/解決策

起動の順でMongoDBの後にNode.jsが起動していない。
よってMongoDBの起動が完了した段階で、Node.jsを起動するためにRocketChatの再起動を行った。

以下、補足です。

補足

MongoDB上でエラーが起きていないにもかかわらず

.. I NETWORK  [listener] connection accepted from xx:36898 #13 (6 connections now open)
.. I NETWORK  [conn13] received client metadata from xx:36898 conn13: { driver: { name: "MongoDB Internal Client", version: "4.0.18" }, os: { type: "Linux", name: "Ubuntu", architecture: "x86_64", version: "16.04" } }
.. [listener] connection accepted from xx:36900 #14 (7 connections now open)
.. I NETWORK  [conn14] received client metadata from xx:36900 conn14: { driver: { name: "MongoDB Internal Client", version: "4.0.18" }, os: { type: "Linux", name: "Ubuntu", architecture: "x86_64", version: "16.04" } }
.. I NETWORK  [listener] connection accepted from xx #15 (8 connections now open)
.. I NETWORK  [conn15] received client metadata from xx:52084 conn15: { driver: { name: "MongoDB Internal Client", version: "4.0.18" }, os: { type: "Linux", name: "Ubuntu", architecture: "x86_64", version: "16.04" } }...

事象欄に記載した通りNode.js側でエラーが発生していました。

状況として、Node.jsとMongoDBが正常に上がっていた状態でMongoDBを再起動しました。
そうすると同事象が発生したので、自動的に再接続が発生しないのかもしれません。

以上、ご参考になれば幸いです。