Can overlayFS support more than two layers?

Question

As far as i read documentation the overlayFS supports two layers - upper and lower. But is there possibility to increase it to three layers?

Answer 1

short answer: yes

long answer: from the sections "Upper and Lower" and "Multiple lower layers":

"...The lower filesystem can be any filesystem supported by Linux and does not need to be writable. The lower filesystem even be another overlayfs. ..."

Answer 2

From the documentation:

Multiple lower layers can now be given using the the colon (":") as a
separator character between the directory names.  For example:
mount -t overlay overlay -olowerdir=/lower1:/lower2:/lower3 /merged

https://www.kernel.org/doc/Documentation/filesystems/overlayfs.txt