我尝试启动mongod并收到此错误
forked process: 4271
ERROR: child process failed, exited with error number 62
To see additional information in this output, start without the "--fork" option.
我尝试了sudo mongod并得到了它
2019-11-26T12:54:27.563-0500 I CONTROL [initandlisten] MongoDB starting : pid=4275 port=27017 dbpath=/data/db 64-bit host=dhcp020-218-083.wireless.buffalo.edu
2019-11-26T12:54:27.563-0500 I CONTROL [initandlisten] db version v4.2.1
2019-11-26T12:54:27.563-0500 I CONTROL [initandlisten] git version: edf6d45851c0b9ee15548f0f847df141764a317e
2019-11-26T12:54:27.563-0500 I CONTROL [initandlisten] allocator: system
2019-11-26T12:54:27.563-0500 I CONTROL [initandlisten] modules: none
2019-11-26T12:54:27.563-0500 I CONTROL [initandlisten] build environment:
2019-11-26T12:54:27.563-0500 I CONTROL [initandlisten] distarch: x86_64
2019-11-26T12:54:27.563-0500 I CONTROL [initandlisten] target_arch: x86_64
2019-11-26T12:54:27.563-0500 I CONTROL [initandlisten] options: {}
2019-11-26T12:54:27.564-0500 I STORAGE [initandlisten] Detected data files in /data/db created by the 'wiredTiger' storage engine, so setting the active storage engine to 'wiredTiger'.
2019-11-26T12:54:27.564-0500 I STORAGE [initandlisten] wiredtiger_open config: create,cache_size=7680M,cache_overflow=(file_max=0M),session_max=33000,eviction=(threads_min=4,threads_max=4),config_base=false,statistics=(fast),log=(enabled=true,archive=true,path=journal,compressor=snappy),file_manager=(close_idle_time=100000,close_scan_interval=10,close_handle_minimum=250),statistics_log=(wait=0),verbose=[recovery_progress,checkpoint_progress],
2019-11-26T12:54:28.082-0500 I STORAGE [initandlisten] WiredTiger message [1574790868:81997][4275:0x114a835c0], txn-recover: Recovering log 35 through 36
2019-11-26T12:54:28.131-0500 I STORAGE [initandlisten] WiredTiger message [1574790868:131917][4275:0x114a835c0], txn-recover: Recovering log 36 through 36
2019-11-26T12:54:28.180-0500 I STORAGE [initandlisten] WiredTiger message [1574790868:180756][4275:0x114a835c0], txn-recover: Main recovery loop: starting at 35/896 to 36/256
2019-11-26T12:54:28.259-0500 I STORAGE [initandlisten] WiredTiger message [1574790868:259184][4275:0x114a835c0], txn-recover: Recovering log 35 through 36
2019-11-26T12:54:28.306-0500 I STORAGE [initandlisten] WiredTiger message [1574790868:306249][4275:0x114a835c0], txn-recover: Recovering log 36 through 36
2019-11-26T12:54:28.345-0500 I STORAGE [initandlisten] WiredTiger message [1574790868:345839][4275:0x114a835c0], txn-recover: Set global recovery timestamp: (0,0)
2019-11-26T12:54:28.399-0500 I RECOVERY [initandlisten] WiredTiger recoveryTimestamp. Ts: Timestamp(0, 0)
2019-11-26T12:54:28.405-0500 I STORAGE [initandlisten] Timestamp monitor starting
2019-11-26T12:54:28.405-0500 I CONTROL [initandlisten]
2019-11-26T12:54:28.405-0500 I CONTROL [initandlisten] ** WARNING: Access control is not enabled for the database.
2019-11-26T12:54:28.405-0500 I CONTROL [initandlisten] ** Read and write access to data and configuration is unrestricted.
2019-11-26T12:54:28.405-0500 I CONTROL [initandlisten] ** WARNING: You are running this process as the root user, which is not recommended.
2019-11-26T12:54:28.405-0500 I CONTROL [initandlisten]
2019-11-26T12:54:28.405-0500 I CONTROL [initandlisten] ** WARNING: This server is bound to localhost.
2019-11-26T12:54:28.405-0500 I CONTROL [initandlisten] ** Remote systems will be unable to connect to this server.
2019-11-26T12:54:28.405-0500 I CONTROL [initandlisten] ** Start the server with --bind_ip <address> to specify which IP
2019-11-26T12:54:28.405-0500 I CONTROL [initandlisten] ** addresses it should serve responses from, or with --bind_ip_all to
2019-11-26T12:54:28.405-0500 I CONTROL [initandlisten] ** bind to all interfaces. If this behavior is desired, start the
2019-11-26T12:54:28.405-0500 I CONTROL [initandlisten] ** server with --bind_ip 127.0.0.1 to disable this warning.
2019-11-26T12:54:28.405-0500 I CONTROL [initandlisten]
2019-11-26T12:54:28.405-0500 I CONTROL [initandlisten]
2019-11-26T12:54:28.405-0500 I CONTROL [initandlisten] ** WARNING: soft rlimits too low. Number of files is 256, should be at least 1000
2019-11-26T12:54:28.407-0500 I SHARDING [initandlisten] Marking collection local.system.replset as collection version: <unsharded>
2019-11-26T12:54:28.408-0500 F CONTROL [initandlisten] ** IMPORTANT: UPGRADE PROBLEM: Found an invalid featureCompatibilityVersion document (ERROR: BadValue: Invalid value for version, found 3.6, expected '4.2' or '4.0'. Contents of featureCompatibilityVersion document in admin.system.version: { _id: "featureCompatibilityVersion", version: "3.6" }. See http://dochub.mongodb.org/core/4.0-feature-compatibility.). If the current featureCompatibilityVersion is below 4.0, see the documentation on upgrading at http://dochub.mongodb.org/core/4.0-upgrade-fcv.
2019-11-26T12:54:28.408-0500 I NETWORK [initandlisten] shutdown: going to close listening sockets...
2019-11-26T12:54:28.408-0500 I NETWORK [initandlisten] removing socket file: /tmp/mongodb-27017.sock
2019-11-26T12:54:28.408-0500 I - [initandlisten] Stopping further Flow Control ticket acquisitions.
2019-11-26T12:54:28.408-0500 I STORAGE [initandlisten] Deregistering all the collections
2019-11-26T12:54:28.408-0500 I STORAGE [initandlisten] Timestamp monitor shutting down
2019-11-26T12:54:28.408-0500 I STORAGE [initandlisten] WiredTigerKVEngine shutting down
2019-11-26T12:54:28.408-0500 I STORAGE [initandlisten] Shutting down session sweeper thread
2019-11-26T12:54:28.408-0500 I STORAGE [initandlisten] Finished shutting down session sweeper thread
2019-11-26T12:54:28.408-0500 I STORAGE [initandlisten] Shutting down journal flusher thread
2019-11-26T12:54:28.499-0500 I STORAGE [initandlisten] Finished shutting down journal flusher thread
2019-11-26T12:54:28.500-0500 I STORAGE [initandlisten] Shutting down checkpoint thread
2019-11-26T12:54:28.500-0500 I STORAGE [initandlisten] Finished shutting down checkpoint thread
2019-11-26T12:54:28.500-0500 I STORAGE [initandlisten] Downgrading WiredTiger datafiles.
2019-11-26T12:54:28.576-0500 I STORAGE [initandlisten] WiredTiger message [1574790868:576019][4275:0x114a835c0], txn-recover: Recovering log 36 through 37
2019-11-26T12:54:28.615-0500 I STORAGE [initandlisten] WiredTiger message [1574790868:615152][4275:0x114a835c0], txn-recover: Recovering log 37 through 37
2019-11-26T12:54:28.666-0500 I STORAGE [initandlisten] WiredTiger message [1574790868:666135][4275:0x114a835c0], txn-recover: Main recovery loop: starting at 36/2048 to 37/256
2019-11-26T12:54:28.744-0500 I STORAGE [initandlisten] WiredTiger message [1574790868:744560][4275:0x114a835c0], txn-recover: Recovering log 36 through 37
2019-11-26T12:54:28.790-0500 I STORAGE [initandlisten] WiredTiger message [1574790868:790388][4275:0x114a835c0], txn-recover: Recovering log 37 through 37
2019-11-26T12:54:28.831-0500 I STORAGE [initandlisten] WiredTiger message [1574790868:831263][4275:0x114a835c0], txn-recover: Set global recovery timestamp: (0,0)
2019-11-26T12:54:28.964-0500 I STORAGE [initandlisten] shutdown: removing fs lock...
2019-11-26T12:54:28.965-0500 I CONTROL [initandlisten] now exiting
2019-11-26T12:54:28.965-0500 I CONTROL [initandlisten] shutting down with code:62```
我已经检查过是否有一个/ data / db文件夹，并且确实这样做，我试图删除data文件夹并重新创建它，但是没有运气。我在论坛上进行了检查，错误代码62表示data / db文件夹的版本与MongoDB安装的版本不同，我不确定如何解决此错误。