[SOLVED] WARN: old systemd (< v232) detected, container won't run in a pure cgroupv2 environment! after modifying systemd.unified_cgroup_hierarchy=0

[barlap]

Hello folks,
I just installed Proxmox VE 8.2.4 on 2 machines and set them in a cluster:
Machine 1: EXT4 configuration - Mini pc: 4 x Intel(R) Celeron(R) J4125 CPU @ 2.00GHz (1 Socket | 8GB RAM | SSD M2 240GB + SATA3 480GB in EXT4 configuration
Machine 2: ZFS-RAID1 - Mini pc: 8 x Intel(R) Core(TM) i7-6700T CPU @ 2.80GHz (1 Socket) | 16GB RAM | SSD M2 1TB + SSD SATA3 1TB in ZFS configuration (Mirror)

The idea is that I want to run an old web compiler that requires Centos7.
I downloaded the official LXC container images from http://download.proxmox.com/images/system/ (centos-7-default_20190926_amd64.tar.xz ) and set it up on my first machine by updating the grub config (open /etc/default/grub and edit/add GRUB_CMDLINE_LINUX_DEFAULT="quiet systemd.unified_cgroup_hierarchy=0" then update-grub and reboot node).
This worked on the first machine and I could successfully boot into centos 7 LXC container.
When I tried the same thing on the second machine that is more powerful and also is configured in ZFS the WARN: old systemd (< v232) detected still persists.
Did I do something wrong?

 

[barlap]

Fixed it.
The issue was that second server running zfs was using systemd-boot instead of GRUB so I had to manually add "quiet systemd.unified_cgroup_hierarchy=0" into the "/etc/kernel/cmdline" file then reboot and everything worked.