I know the official docs recommend Ubuntu 16.04, but are there any show-stoppers for Ubuntu 18.04 LTS Minimal (as offered in Google Cloud Compute) with regard to Discourse?
EDITED with an extra question: 
How much storage space should I make available to Discourse? I’m currently using an SSD 15GB allowance. Our forum, however, will have millions of posts imported. How much space should be realistically allocated for a forum of such size?
It should work, though I’ve not tested it.
I’d recommend at least 50GB. Once you’ve got things up and running you can take stock of how much space you’re actually using.
Try minimal and let us know how it works — I hope it does work!
The answer depends in part on how many pictures etc. you expect your users to upload. We transitioned to Discourse from a homemade forum on top of a bunch of Majordomo mailing lists. On our old platform, uploads were a non-issue. Once we switched to Discourse and people discovered the joys of posting inline pictures, our uploads exploded.
We have about 100k registered users, of which 40k are active. We have 1.9 million messages (about 5 GB worth of text) and about 18 GB in uploads. Those 18 GBs all showed up in the last two years, since we switched.
You can elect to store uploads in S3 on AWS, that’ll save you on local disk space. Same with backups.
Even if you do use S3, if your forum is the same size or larger than ours, I’d go with 80-100 GB of disk. It’s good to have some elbow room, just in case.
Right now, with two backups stored locally, older backups in S3 and all uploads in S3, our server still weighs in at a hefty 54 GB.
Good luck!
Gunnar
I can confirm it does works!
I’m using 18.04.1 also and works fine.
Replying to my own post to confirm, yes 18.04 LTS Minimal works for me (so far)!
All I had to do was manually install Git first.
18.04 is supposed to bench faster than 16.04, right? (Mileage for Discourse may vary, though, of course)
Performance mostly depends on the CPU and RAM (the newer the better) OS does have it’s impact but not much noticeable so far.
Can any of you guys running on 18.04 reproduce this problem?
https://meta.discourse.org/t/no-image-preview-for-large-images/94521/3?u=tophee
Works for me… unless you’re referring to something else?
Here’s a huge image I posted to the Site Assets topic:
Clicked on it and got the bigger image that you see in this screenshot:
Clicked on the bigger image and got it ZOOMED IN (with browser scrollbars) like in this screenshot:
Hmmm, don’t know what to say. I Installed Ubuntu 18.04 LTS twice with discourse, both times I could not get large images to show a preview. I done the exact same process except this time using Ubuntu 16.04 LTS and image previews worked fine for me. The assumption was Ubuntu 18.04 LTS was the problem, if its not I would be happy to be pointed at any troubleshooting tips to identify the root cause of the issue.
I used the 18.04 LTS Minimal image provided on Google Cloud Compute. The only thing I had to do before installing Discourse was to manually install Git first.
I used the .iso directly from ubuntu site - ubuntu-18.04-live-server-amd64.iso
This may well be something my end, I’m no expert. All I can say is, using Ubuntu 18.04 LTS gave me no image previews, when I followed the exact same process but on Ubuntu 16.04 LTS, I didn’t have the issue. Maybe I inadvertently done something different on the Ubuntu 18.04 LTS OS Installation?
I used Digital Ocean and ran do-release-upgrade to 18.04.1. Upgrade went fine and Discourse runs fine.
