We've been having diskspace problems on one of our Zimbra servers for a couple of months now, mainly because it isn't particularly big (~100GB). To help it out, I added a secondary volume (an NFS mounted partition from a NAS box) and started running HSM.
Unfortunately, our usage is growing exponentially, and all I can do now is to keep reducing the age threshold for HSM more and more. I've got it at 90 days now, which is repidly getting to the point that far too recent mail is going to get moved by HSM.
I noticed just now that when the inital volume was set up on this server, it seems compression was turned off on the message volume. Is there any way to apply compression to blobs already on a volume? I'm surmising that I have some 90GB of blobs that would benefit greatly from being compressed and would love to be able to recurse over the volume with some magic utility, compressing the blobs as it finds them :-)
PS. Network mounted disks are my only hope for this box at present - a lack of foresight on my part used 1U servers with both disks filled, with the intention of connecting them to a SAN. The budget for the SAN was pulled...