Mongo service crashed. Need to find reason of crash

Question

Today morning I found the following error with mongo, on my server.

*** System restart required ***
You have mail.
ubuntu@ip-xxx-xx-xx-xx:~$ mongo
MongoDB sh         


        

Answer 1

My server also crashed for no obvious reason. The other answers did not throw anything. But I found the following looking at the mongod.conf file in /etc/.

There are also logs inside /var/log/mongodb/mongod.log. It seems that by default it has a 500 Mb limit. But is still a big file.

There I found that my server crashed at a certain time, but couldn't find the reason.

2019-04-17T19:39:11.700+0000 I COMMAND  [conn460] command cge_info_system.expedientes command: find { find: "expedientes", filter: { NoExpediente: "090311-497449" }, limit: 1, $db: "cge_info_system", $readPreference: { mode: "primaryPreferred" }, lsid: { id: UUID("f18d952b-37e7-4a45-bf31-b89a596057d1") } } planSummary: COLLSCAN keysExamined:0 docsExamined:49360 cursorExhausted:1 numYields:386 nreturned:1 reslen:3224 locks:{ Global: { acquireCount: { r: 387 } }, Database: { acquireCount: { r: 387 } }, Collection: { acquireCount: { r: 387 } } } protocol:op_msg 1416ms
2019-04-23T16:35:19.578+0000 I CONTROL  [main] ***** SERVER RESTARTED *****
2019-04-23T16:35:19.599+0000 I CONTROL  [main] Automatically disabling TLS 1.0, to force-enable TLS 1.0 specify --sslDisabledProtocols 'none'
2019-04-23T16:35:19.958+0000 I CONTROL  [initandlisten] MongoDB starting : pid=741 port=27017 dbpath=/var/lib/mongodb 64-bit host=bb7dd22f-cb77-4c6b-9c4c-9fddcfc2cc00.clouding.host
2019-04-23T16:35:19.958+0000 I CONTROL  [initandlisten] db version v4.0.5
2019-04-23T16:35:19.958+0000 I CONTROL  [initandlisten] git version: 3739429dd92b92d1b0ab120911a23d50bf03c412
2019-04-23T16:35:19.958+0000 I CONTROL  [initandlisten] OpenSSL version: OpenSSL 1.1.0g  2 Nov 2017
2019-04-23T16:35:19.958+0000 I CONTROL  [initandlisten] allocator: tcmalloc
2019-04-23T16:35:19.958+0000 I CONTROL  [initandlisten] modules: none
2019-04-23T16:35:19.958+0000 I CONTROL  [initandlisten] build environment:
2019-04-23T16:35:19.958+0000 I CONTROL  [initandlisten]     distmod: ubuntu1804
2019-04-23T16:35:19.958+0000 I CONTROL  [initandlisten]     distarch: x86_64
2019-04-23T16:35:19.958+0000 I CONTROL  [initandlisten]     target_arch: x86_64
2019-04-23T16:35:19.958+0000 I CONTROL  [initandlisten] options: { config: "/etc/mongod.conf", net: { bindIp: "127.0.0.1", port: 27017 }, processManagement: { timeZoneInfo: "/usr/share/zoneinfo" }, storage: { dbPath: "/var/lib/mongodb", journal: { enabled: true } }, systemLog: { destination: "file", logAppend: true, path: "/var/log/mongodb/mongod.log" } }
2019-04-23T16:35:19.961+0000 W STORAGE  [initandlisten] Detected unclean shutdown - /var/lib/mongodb/mongod.lock is not empty.
2019-04-23T16:35:19.962+0000 I STORAGE  [initandlisten] Detected data files in /var/lib/mongodb created by the 'wiredTiger' storage engine, so setting the active storage engine to 'wiredTiger'.
2019-04-23T16:35:19.962+0000 W STORAGE  [initandlisten] Recovering data from the last clean checkpoint.
2019-04-23T16:35:19.962+0000 I STORAGE  [initandlisten]

In there is also a reference to a directory called /var/lib/mongodb/diagnostic.data but the data in there are binary files. I haven't got much info from there.