tutorial for ipv6 on Proxmox and client (VM)

The same way you use it on a physical machine.
 
i have a VM with Debian 8.5 jessie
vi /etc/network/interfaces

10 # The primary network interface
11 allow-hotplug eth0
12 iface eth0 inet static
13 address 10.147.42.63
14 netmask 255.255.255.0
15 gateway 10.147.42.1
16
17 auto he-ipv6
18 iface he-ipv6 inet6 v4tunnel
19 address 2001:470:25:31f::c14
20 netmask 64
21 endpoint 216.66.80.98
22 local 85.6.218.42
23 ttl 255
24 gateway 2001:470:25:31f::1

it is possible to ping the Gateway from outside

from outside i can't ping the VM
the VM can't ping himself (ping: unknown host 2001:470:25:31f::c14)
the VM can't ping the Gateway

vi /etc/hosts
2001:470:25:31f::c14 munin.kozo.ch
 
Is the firewall active? Are the settings correct? Can you successfully use this configuration on the host machine?
 
the should be no Firewall!
with ipv4 i Access the host without Problem in the LAN, of corse not from outside!
But i found out there is a possibility to crate some new vmbr and add ipv6 Information -- but they make all Errors when creating it.