Upgrading from MongoDB 3.0 to 4.4

[Stennie_X (Stennie)]

@Evan_L

I’m wondering if dumping the database using mongodump , then updating directly to mongoDB 4.4, and finally restoring the database using mongorestore can work, and if there any disadvantages or complications we need to be aware of. Any ideas?

Hi @Evan_L,

Successive in-place upgrades are the most thoroughly tested approach and will minimise downtime.

However, if downtime is acceptable (and you’re open to hitting a few fixable speedbumps along the way), mongorestore is definitely a possibility.

Please see my comment on Replace mongodb binaries all at once? - #3 by Stennie_X for more elaboration on alternatives to in-place upgrades.

The mongorestore path is the last option discussed in my comment:

@Stennie_X

Upgrade with Backups & Downtime

If downtime is acceptable and you have a large number of major releases to upgrade through, you can also consider a migration using mongodump and mongorestore .

This approach will require more testing and patience because you are still subject to major version compatibility changes and will encounter different issues depending on the provenance of your data. This approach will also not support upgrading user & auth schema, which is supported via the usual in-place upgrade path.

Unlike an in-place upgrade, dump & restore will recreate all data files and indexes so you may run into some (fixable) errors. The most likely complaints will be due to stricter validation of index and collection options which would not cause an issue for an in-place upgrade. I definitely recommend testing this procedure in a staging/QA environment with a copy of your production data to ensure there are no unexpected issues that might otherwise delay your production upgrade.

Regards,
Stennie