Question on AUFS and OverlayFS


(Reece) #1

Background: I’m relatively new to Docker, but have extensive *nix experience. In my personal life I’ve run mostly Ubuntu, but lately I’ve been trying to run Fedora or CentOS as we’re 100% RHEL at work and I’m tired of typing “apt-get” when I should be typing “yum”. :smile:

So trying to get Discourse running on Fedora per the Install guide has been… enlightening. Every thread I read, all of my googling, pointed to AUFS as being the only workable solution. Not a huge deal, I’ve been recompiling kernels for twenty years. But since it seems AUFS is never going to be merged, it’s certainly not ideal.

I guess my question is, is there a strong reason to use AUFS over OverlayFS? Overlay has been merged since 3.18 (and backported to RHEL7), Docker supports it now (on EXT4). Sure, SELinux has issues, but those are going to be solved eventually. And now I’m not limited to Ubuntu for an out-of-the-box Discourse install, which is fantastic because I’ve been wanting to use it at work.

I have Discourse bootstrapped on Fedora without error and everything appears to be running great… but are there known issues that could bite me down the road?


(Sam Saffron) #2

OverlayFS support was just added in Docker 1.4 - 1.5, so it is less tested and may have kinks. That said, it is probably workable and supposedly the fastest backend available. The only engine I strongly recommend avoiding is device mapper, cause it is both hacky and broken.

(Sam Saffron) #3

Note… on local:

Its looking pretty fast, but you need to keep an eye on inode counts with df -i