I've taken over managing a site running Silverstripe 3.1.1 and recently had to migrate it to a new machine. Now the content managers are having issues updating content. Often they will press the publish button and their changes will disappear. The changes will turn up in the History tag under the unpublished versions section. Reverting to that version of page then moves it to the published section but does not make it the live version. To make it worse I have reports of attempts to make change "failing", confirming the changes did not go through, but the next day the change appears on the website.

I can't do an update as there is some custom code and I don't have time to update it all. I've switched things to dev mode and checked the js console but I'm not getting any new warnings or errors. I can run dev/build and flush successfully. Otherwise the site is working fine with no problems.
At this point I'm also out of ideas on how to diagnose this issue.

Old Machine: Ubuntu 12.04; Apache 2.2; MySQL 5.5
New Machine: Ubuntu 14.04; Apache 2.4; MySQL 5.6

I'm new to silverstripe so please feel free to assume I missed something basic and offer any suggestions on where to look.

You should actually be able to update to 3.1.15. I seem to recall that it solves some issues with Apache 2.4, although I don't know if that has anything to do with your problem.

I've found myself thinking I pushed publish, but actually ending up only on 'save' because that button suddenly became wider, so that may be an issue?

If a change doesn't become visible until the next day, could it have something to do with some sort of caching system on your new server?

Wat I would definitely try is install a copy of your site (on the same server, if possible), and then update SilverStripe CMS and framework to 3.1.15 and see what that does first...

I tried the 3.2 update but that messed up the custom code. If the transition to 3.1.15 is a clean one that's my best bet. I'll try it right away.

I've actually gone and looked over their shoulders on this one. They are pressing the publish button.

I've had similar thoughts about there being some sort of caching issue but its a new machine and we haven't even turned on caching yet. I have double checked the most commonly used ones and made sure they have been disabled. As always there may be one or two hiding somewhere screwing things up but I haven't found them yet.

Version 3.1.15 should work. Version 3.2 might not out of the box, since its API has undergone some changes:

https://docs.silverstripe.org/en/3.2/changelogs/3.2.0/

[edit] as to caching: silverstripe has its own internal caching system, but that takes some getting used to. Maybe it hasn't been implemented correctly, so publishing doesn't reset the cache right away? Check for the use of <% cache ... In your template files, or look into htaccess to see if some static html caching is used?

Upgrading SS to 3.1.15 seems to have fixed the major issues we were seeing. There were a few problems with some installed modules but that was due to a previous upgrade. Apparently the person at the time tweaked the modules instead of just updating them. Still going to look at the cache system but things look stable at the moment..