Hi All,
I'm wondering if I have a problem, or if I just don't understand something correctly. Here's the situation. When we built a new server, we created separate primary and secondary mailstore disks. We calculated the size of the primary disk based on our complete volume of messages from the old server and thought we'd have enough space to hold several months of mail in the primary.
(Actually we started with importing all mail from the old server into a Primary that was built to be the long-term Secondary, a much larger disk. Then once the import was complete, we moved the initial Primary to Secondary and set the smaller disk to Primary.)
Once we re-assigned Primary and Secondary, we started out with HSM settings to keep 30 days on the Primary, then move to compressed Secondary. This worked fine and we began filling the Primary. I don't remember the percentage used on the Primary when we hit 30 days and the HSM started moving blobs to the secondary. I wasn't watching it closely and assumed we'd have plenty of space.
Over time, we ended up with the Primary filling to 80 then 90%. So I changed the HSM policy to 24 days. A lot of blobs were moved and we dropped our usage of the Primary disk. But then it continued to creep back up to 80-90% again. Dropped the HSM again.. Filled up again... Dropped again... etc....
Today we had been down to only 12 days in the policy and were filling up again. When I dropped it from 12 days to 10 days just now, we freed up 11% of the space on the Primary. But statistically, it should have moved over 16% since we moved 2 of 12 days.
We don't seem to be receiving exponentially more email, so it seems that something isn't getting moved from Primary to Secondary. Is there any way to figure out what's happening? HSM Policy is set to move all items (except chats - we don't use chat). The logs indicate that some blobs are being moved every day.
At this point, if I understand the HSM policy, the Primary mailstore should only have the last 10 days of "anything" stored there. Currently that disk is using 25GB of space. Our secondary, which I think has everything older than 10 days is using 388GB. The secondary IS compressed, and has had deduplication run a few times. But it has several years of email. At the rate of 25GB for 10 days, then a year should consume over 900GB. I know that compression and deduplication (and junk and trash cleanup) will make a difference, but it seems like something is out of whack.
Trying to look at file ages on the Primary mailstore, we ran this command:
find /primarymailstore/0/ -type f | wc -l (should give current file count) and the result was 186824.
find /primarymailstore/0/ -type f -mtime +12 | wc -l (should give count of files modified more than 12 days ago) gave a result of 88281.
Some of these files with older modified dates go back to August. We shifted to the new server in July, and it was probably some time in August when we moved the original Primary to Secondary and implemented the new smaller Primary disk.
Sorry this is so long. Just trying to get as much information out there. I'd appreciate any ideas what could be causing this! If I'm not understanding how the HSM policy should be working, let me know that too. 
Thanks!
Brad
Zimbra version: 8.6.0, patch 3. Zextras version: 2.0.3 OS: CentOS 6.6