Create admin user

1. Create user:

USER="asd"; \
PASS="asd"; \
COMMENT="System Administrator"; \
if ! id "$USER" &>/dev/null; then \
  sudo useradd -m -s /bin/bash "$USER" && echo "$USER:$PASS" | sudo chpasswd; \
fi; \
pveum groupadd admin --comment "${COMMENT} group" 2>/dev/null; \
pveum aclmod / --group admin --role Administrator; \
pveum useradd "${USER}@pam" --comment "${COMMENT}" --groups admin 2>/dev/null

2. Remove:

USER="asd"; \
sudo deluser --remove-home "$USER"; \
pveum user delete "${USER}@pam" 2>/dev/null; \
pveum group remove admin 2>/dev/null

3. Disable root access for GUI (optional):

pveum user modify root@pam --enable 0

There are cases when you need it, to enable:

pveum user modify root@pam --enable 1