MONGODB_CONFIG_OVERRIDE_NOFORK after upgrade to 5.18

Ops and Admin Installation & Upgrades
1

Hi, just updated my test server (Ubuntu 20.04) from a previous 5.x release to 5.18 and I’m now getting this error when restarting:

Environment variable MONGODB_CONFIG_OVERRIDE_NOFORK == 1, overriding “processManagement.fork” to false

Mongod is configured to run as a single-node replicaset on this server, more details here:

storage:
  dbPath: /var/lib/mongodb
  journal:
    enabled: true
  oplogMinRetentionHours: 24

systemLog:
  destination: file
  logAppend: true
  logRotate: reopen
  path: /var/log/mongodb/mongod.log

net:
  port: 27017
  bindIp: 127.0.0.1

processManagement:
  timeZoneInfo: /usr/share/zoneinfo
  fork: true
  pidFilePath: /run/mongodb/mongod.pid

replication:
  replSetName: test-replica-name
2

Check this link

3

I saw this, but it comes with no explanation and looks like a word-around more than a proper solution.

4

What does mongod.log shows
So mongod does not start?

5

Mongod does start, but systemd doesn’t detect it as running so it then triggers a shutdown. I’m using the default unit file. All of this is related to the changes down starting with 5.15 related to forking.

If I remember correctly, forking was needed to achieve a sane behavior with logrotate.

6

Try to comment the fork parameter in config file and start the service
May be it is already taken care in the mongod.service

7

I reverted to 5.13 until I have a better understanding of this.

8

Hi @Jean-Francois_Lebeau

Please note that MongoDB 5.13, 5.15, and 5.18 are not official MongoDB versions. Did you mean MongoDB 5.0.18 instead?

Either way, could you post how did you install MongoDB, and whether you’re using Docker or similar?

Best regards
Kevin

9

Obviously I meant 5.0.x. No docker, standard Ubuntu install (apt).

5.0.13 works with the forking option, but not 5.0.18, I recall that forking was needed for logrotate.