The ZFS filesystem has many features that once you try them you can never go back. One of the lesser known is probably the support for replicating a zfs filesystem by sending the changes over the network with zfs send/receive.
Technically the filesystem changes don't even need to be sent over a network: you could as well dump them on a removable disk, then receive from the same removable disk.
I was recently asked to recover a mirth instance whose embedded database had grown to fill all available space so this is just a note-to-self kind of post.
Btw: the recovery, depending on db size and disk speed, is going to take long.
A 1.8 Mirth Connect instance was started, then forgotten (well neglected, actually). The user also forgot to setup pruning so the messages filled the embedded Derby database until it grew to fill all the available space on the disk.
The SO is linux.
First of all: free some disk space so that the database can be started in embedded mode from the cli. You can also copy the whole mirth install to another server if you cannot free space. Depending on db size you will need a corresponding amount of space: in my case a 5GB db required around 2GB to start, process logs and then store the temp files during shrinking.
Then open a shell as the user that mirth runs as (you're not running it as root, are you?) and cd into the mirth home. …
NGINX has had support for dynamic upstream modules for a while in the community distribution and examples abund. I think this is probably one of the clearest I could find.
Finding a similar config for stream proxies turned out to be surprisingly hard, so here I'm sharing my solution in the hope that it can be useful to somebody. Or someone more experienced can point out a better alternative.
In my case my upstream is an ELB which can and will change ip address often so using the static DNS name was not an option.