Linode volumes, resizing

I think you can resize the volume while it is in use, but in order for the resize to be effective, I believe you need to either reboot the Linode it's attached to, or unmount and reattach it, resize any file system or partition you have on the volume, then remount it. It's been a while since I've done this, so I could be wrong. You shouldn't lose any data when you resize the volume while it's in use, though.

How I want to use this:

I have a Linode volume, I am running LUKS and LVM on top of it, and will have an ext4 filesystem on top of all that.

I know you can grow the size of an ext4 filesystem while it is mounted, and I can grow the size of an LVM logical volume while it is in use as well, so if I can extend the size of a Linode volume I should be able to do this all on the fly.

The intent is to use said volume as storage for Mongodb, and a requirement is that we be able to grow the storage space without bringing the database down.

I'd say try it on a temporary setup and see what happens there, I think that's the only way to know for sure if it'll work for you how you want to use it.