Can't create Sqlite database in mounted volume

Questions / Help
1

Recently I’ve been trying to scale my app to two regions, but am having trouble with writing data to the volume of the new region.

  1. I added a volume with matching name to the lax region
  2. Ran fly scale count 2
  3. Saw in flyctl logs that my app is unable to create/read a Sqlite database on the volume upon launching.

The weird bit is it works absolutely fine in the original region I deployed to (ams), and has done so for the last four months. My app uses the heroku/buildpacks:20 builder, could anything have changed under my feet?

Unfortunately better-sqlite3 doesn’t give me much more information than SqliteError: unable to open database file.

2

Would you mind sharing the script that does the DB file init?

Only possible solution that I can think of right now is that the second volume isn’t automatically replicated, so you might have to create the DB file again there (if you haven’t done so already).

3

@sudhir.j There’s a few layers of abstraction, but it boils down to making an instance of better-sqlite3’s Database class:

let db = new Database(path);

This will create a new file if none is found at the given path (which is /data/mydb.sql).

For whatever reason, this operation fails on a newly deployed instance in another region, although it works every time in ams.

4

Looks like you’re doing everything right, let me get this in front of the team. Which app ID is this?

5

fragrant-leaf-492. Thanks!

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6

This is probably a permissions error. If you ssh to your instance and run ls -la /data you can see who owns it. If that path, or any file within that path, is owned by root, that’s a problem. You can likely fix it by running chown -R heroku:heroku /data.

We try and set ownership when we first mount a volume but this is a relatively complex problem and we haven’t figured out the perfect UX yet.

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8

@kurt That was it! Thanks.