Proxmox won't start after IP change

[sixund ohms]

SOLVED !

Fabian & Wolfgang, thank you very much for your time and patience. That was driving me mad.

1. /etc/hosts (my hostname is "myhostname.org")
127.0.0.1 localhost
192.168.1.70 proxmox myhostname.org

When i ping myhostname.org it must resolve to the ip and not 127.0.0.1

2. /etc/pve was not empty .
# mv /etc/pve /etc/pve-old (just in case...)

then

# systemctl start pve-cluster.service

SUCCESS. A nice reboot and /etc/pve populated again and web interface is back !

Thank you again.