Edit: **this will make your oci instance less secure **and will break integrations with other oci services. Do not use this in production, but ONLY for testing if the host fw rules affect your app.
I'm currently using oraclecloud for my bots. I work in the space (cloud/systems engg) and the first thing that got me was that the oracle ubuntu instances have custom iptables in place for security.
I'm not sure if it still has, but last i checked a year ago I had to flush iptables before I was able to use other ports. I didint really want to deal with another layer of security to manage as I was just using the arm servers for my hobby.
It might be something worth checking, it isn't specific to lemmy though.
I found it unintuitive because other major cloud providers do not have any host firewall/security in place (making it easier to manage security using SG/NACL, through the console).
I agree with this, what I suggested is not a best practice, I should preface my post with that.
And I feel your pain! I get calls that are extremes, like people putting too much security where the ticket is "P1 everything is down, fly every engineer here" for an nACL/SG they created.
The other extreme is that deliberate exposure of services to the public internet (other service providers send us an email and ask us to do something about it, but not our monkeys, shared responsibility, etc).