ExecStart=/usr/bin/mongod $OPTIONS (code=exited, status=62)

Ops and Admin Installation & Upgrades
1

My DB runs in AWS and I upgraded to Mongo 5.0. Now I cannot even start the it because I get the the following error:

mongodb ERROR: child process failed, exited with "error number 62"

According to the docs it means that there is an incompatibility issue.

I would like to downgrade back to 4.4 but there is no clear way to do so. Mongo Docs assumes the DB is running and says to run db.adminCommand( { setFeatureCompatibilityVersion: "4.4" } )

I can’t run this command since the DB won’t even start.

Is there a way to delete just the 5.0 binaries? My logic is, if the upgrade isn’t there, it’ll roll back to 4.4

Any help you can provide would be greatly appreciated

2 
mongod.service - MongoDB Database Server
   Loaded: loaded (/usr/lib/systemd/system/mongod.service; enabled; vendor preset: disabled)
   Active: failed (Result: exit-code) since Mon 2021-10-25 00:16:42 UTC; 26min ago
     Docs: https://docs.mongodb.org/manual
  Process: 3888 ExecStart=/usr/bin/mongod $OPTIONS (code=exited, status=62)
  Process: 3886 ExecStartPre=/usr/bin/chmod 0755 /var/run/mongodb (code=exited, status=0/SUCCESS)
  Process: 3883 ExecStartPre=/usr/bin/chown mongod:mongod /var/run/mongodb (code=exited, status=0/SUCCESS)
  Process: 3881 ExecStartPre=/usr/bin/mkdir -p /var/run/mongodb (code=exited, status=0/SUCCESS)

This is more output from the error

3

Do you have backup of your data.Best thing is to install latest version and restore the data
downgrade steps given in the mongo documentation but first step is to have all nodes up and running(which is not happening in your case)
Check this link.Some fixes given