I’m currently struggling with upgrading some Postgres DBs on my home-k3s and I’m seriously considering throwing it all away since it’s such a hassle.

So, how do you handle DBs? K8s? Just a regular daemon?

  • bigredgiraffe@lemmy.worldEnglish
    3·
    1 year ago

    Are we talking database schema migrations or migrating a database between Postgres instances?

    If it’s the former, the pattern is usually to run them in init containers or Jobs but I have been wanting to try out SchemaHero for a while which is a tool to orchestrate it and looks pretty neat.

    ETA: Thought I was replying to your below comment but Memmy deleted it the first time for some reason, my bad.

    • AggressivelyPassive@feddit.deOPEnglish
      1·
      1 year ago

      It’s about PostgreSQL upgrade.

      The “pattern” there is to either dump and reinsert the entire DB or upgrade by having two installations (old and new version), which doesn’t exactly work well in k8s. It’s possible, but seems hacky

      • bigredgiraffe@lemmy.worldEnglish
        4·
        1 year ago

        I can’t think of any situation other than maybe wanting to get better indexing or changing the storage engine that I would need to re-create and re-insert that way so I’m not sure if you have a constraint that necessitates that or not but now I’m curious and I am always curious to find new or better methods so why do you do it that way?

        At home to upgrade Postgres I would just make a temporary copy the data directory as a backup and then just change the version of the container and if it’s needed run pg_upgrade as jobs in kubernetes.

        In a work environment there is more likely to be clustering involved so the upgrade path depends on that but it’s similar but there really isn’t a need to re-create the data, the new version starts with the same PVCs using whatever rollout strategy applies. Major version upgrades can sometimes require extra steps but the engine is almost always backwards compatible at least several versions.

      • cdombroski@programming.devEnglish
        1·
        1 year ago

        I’ve always used this docker image to do pg upgrades. It runs pg_upgrade to recreate the system tables and copy the user tables (which normally don’t have any storage changes). It does require that the database isn’t running during the upgrade so you’re going to have a bit of downtime. Make sure you redo any changes to any configuration files, especially pg_hba.conf

  • metaStatic@kbin.social
    41·
    1 year ago

    I google why doesn’t mysqld work?, then copy paste terminal commands from the first result, then google why doesn’t my machine boot? then turn around 360 degrees and walk away.

  • BrianTheeBiscuiteer@lemmy.worldEnglish
    1·
    1 year ago

    Never tried it but kubegres seems like a good implementation for kubernetes. I guess if you just have a single-node cluster there won’t be much benefit but it seems a periodic backup to NFS is key (you can run NFS on most anything).

    • AggressivelyPassive@feddit.deOPEnglish
      2·
      1 year ago

      What currently pisses me off is the fact that it’s almost impossible to do proper migrations for Postgres in k8s. I’d have to look into kubegres, but all approaches I’ve seen so far involve basically copying the entire PVC and the data inside into a new structure - and doing so involves hacked together scripts.

  • exi@feddit.deEnglish
    11·
    1 year ago

    For personal use, I don’t bother with databases on k8s. They are waaay easier to manage if you just let your host distribution run it as a regular service and Upgrade it through that

  • Oliver Lowe@lemmy.sdf.orgEnglish
    01·
    1 year ago

    I avoid software which requires a relational database altogether. For me that’s part of the fun of self hosting: what’s the simplest possible system I can get away with at my tiny scale?