This probably is what it says it is - there are files and/or directories missing from the disk.
Have a look in the Admin -> System info page to see what your "Jira Home" directory is, if you don't already know, then log into the server and check that in that directory, there is a "caches" directory. If there is not, then create one for it.
You should also check the ownership of Jira home and all its subdirectories and files - they should belong to the account that Jira runs as. (Actually, you don't really need to check all of them, on Unix-like systems, you can just issue the fix command of "chown -R jira:jira" assuming the account is called jira)
Once you have made sure the right directory is there and owned by the right user, restart Jira and try a full re-index (not background).
Hi All! We’re excited to share the launch of an announcement banner that lets Jira site administrators communicate directly to their users across Jira Cloud instance. 📢 Get y...
Connect with like-minded Atlassian users at free events near you!Find an event
Connect with like-minded Atlassian users at free events near you!
Unfortunately there are no Community Events near you at the moment.Host an event
You're one step closer to meeting fellow Atlassian users at your local event. Learn more about Community Events