aaron@ubuntu-fl:~⟫ sudo snap install rocketchat-server
[sudo] password for aaron: 
137.54 MB / 137.54 MB [=============================================================================] 100.00 % 5.29 MB/s 

error: cannot perform the following tasks:
- Setup snap "ubuntu-core" (423) security profiles (no state entry for key)
- Setup snap "rocketchat-server" (88) security profiles (cannot setup apparmor for snap "rocketchat-server": cannot load apparmor profile "snap.rocketchat-server.rocketchat-mongo": cannot load apparmor profile: exit status 1
apparmor_parser output:
Cache read/write disabled: interface file missing. (Kernel needs AppArmor 2.4 compatibility patch.)
Warning: unable to find a suitable fs in /proc/mounts, is it mounted?
Use --subdomainfs to override.
)
- Setup snap "rocketchat-server" (88) security profiles (cannot load apparmor profile "snap.rocketchat-server.rocketchat-mongo": cannot load apparmor profile: exit status 1
apparmor_parser output:
Cache read/write disabled: interface file missing. (Kernel needs AppArmor 2.4 compatibility patch.)
Warning: unable to find a suitable fs in /proc/mounts, is it mounted?
Use --subdomainfs to override.
)