Charm needed: NFS

[Ahmed Kamal]

NFS formula needed

[Mark Mims (mark-mims)]

Note

    mediawiki:shared-filesystem nfs-server-1:nfs

[Mark Mims (mark-mims)]

couldn't push to the associated branch, so just attached another. Feel free to remove.

Also added an example of hooks the clients will have to implement.

[Mark Mims (mark-mims)]

I'm done putzing around with this one... sorry that took so long.

The attached branches default to:
 - single server share per service name, so multiple units of the same service share the same directory
 - no_all_squash

You might wanna:
 - nfs4 likes idmapd, but mapping 'ubuntu' to 'ubuntu' should be easier!
 - add root_squash back in for sane security defaults

[Mark Mims (mark-mims)]

Next need to add a couple of example clients into things like mediawiki and drupal.

One remaining problem is in large deploys, the server can get swamped and timeout a mount attempt. Clients should probably be written to be robust against that.

[Mark Mims (mark-mims)]

submitting the nfs-client sub to add to the store.

it takes a local mountpoint as config

TODO: needs to accept local mountpoint via a container-local relation with a primary

note the backflips in getting separate shares from the same server... it works, but perhaps there's a better way to do this?

[Clint Byrum (clint-fewbar)]

Hi Mark! Here's some feedback:

1 The examples in README.md are ok, but its really hard to understand *why* I want this subordinate. The "TODO" of figuring out the dir from the service seems *paramount* to this being clarified. I should not have to configure it for each individual service.. though I get that its useful that way even if the services don't implement this container scoped relation.

2 Commented out stuff in metadata.yaml is just ugly and has no explanatory comments. Just remove it and make a TODO file if you want to keep notes for the future.

3 Default mountpoint of /tmp/data seems wrong. mounts would typically go on top of /srv or /mnt.

4
sed -i -e "s/NEED_IDMAPD.*/NEED_IDMAPD=yes/" /etc/default/nfs-common

should be

sed -i -e "s/NEED_IDMAPD=.*/NEED_IDMAPD=yes/" /etc/default/nfs-common

Otherwise if we ever addd something like NEED_IDMAPD_FOO then this will break that variable... and the only reason to use sed on config files is to preserve forward compatibility.

5 hooks/nfs-relation-changed - changes umask in a function.. seems like that might create unintended consequences later

6 hooks/nfs-relation-changed - this is not really idempotent:

share_already_mounted || mount_share

You should simply add the remount option if its already mounted.. as the other options might have changed.

7 hooks/nfs-relation-departed the umount_share will not cause an error when there is a failure, it will just log "umount failed" but exit 0.

Lots of fun stuff to fix! :)

[Launchpad Janitor (janitor)]

[Expired for Juju Charms Collection because there has been no activity for 60 days.]