If you have followed my previous tutorial on how to batch import your pinned files, you could have easily incurred on this "flatfs: too many open files" error.
Here a practical solution for your Linux OS:
Enter the following folder as superuser via your editor of preference, I'm using nano:
sudo nano /etc/security/limits.conf
add these 2 lines at the end of the file:
. . .
* hard nofile 4096
* soft nofile 40960
# End of file
Log out and log in again > retry =)
4096 and 40960 should be enough, just in case you can always augment these values! ^^
Thank You for reading!
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(it helps me to keep servers running ipfs nodes)