[SOLVED] Network problems with host & guest with subnet (Hetzner root)

Spacey

Renowned Member
Sep 6, 2013
13
5
68
Hi all,

sorry but I already checked out several threads & "wasted" hours with no success so I'm trying it here and I guess you experts can give me a simple & quick solution.

I've got an older rootserver @ Hetzner and used there an pre-configures proxmox 2 debian wheezy installation where it works very well and easy to implement a /29 subnet. I just add a new VM and in the network config screen I enter the new subnet IP in the "Routed mode (venet)" field - est voila, everyting works.

Bildschirmfoto 2016-07-27 um 14.17.59.png

#net.ipv4.ip_forward=1 is commented out - on the "old" server as well as on the new one ->

Now Hetzner got an new Proxmox 4 Debian Jessie image as well and I used for example this tutorial to get it up and running - checked for example lot's of documents like this or that -> I can access the proxmox server itself very well and work there but I can't get no debian 8 guest up regarding the network settings. The guest vm network dialogue is completely different - the whole mechanism seems different with bridge & bond.

My very simple question is what to do and where to get it working?!

I've got a rootserver with an own IP (proxmox is reachable as said) and a /29 subnet for the VMs.


Code:
pveversion --verbose
proxmox-ve: 4.2-58 (running kernel: 4.4.13-2-pve)
pve-manager: 4.2-17 (running version: 4.2-17/e1400248)
pve-kernel-4.4.13-2-pve: 4.4.13-58
pve-kernel-2.6.32-39-pve: 2.6.32-157
pve-kernel-2.6.32-46-pve: 2.6.32-177
lvm2: 2.02.116-pve2
corosync-pve: 2.4.0-1
libqb0: 1.0-1
pve-cluster: 4.0-43
qemu-server: 4.0-85
pve-firmware: 1.1-8
libpve-common-perl: 4.0-71
libpve-access-control: 4.0-18
libpve-storage-perl: 4.0-56
pve-libspice-server1: 0.12.8-1
vncterm: 1.2-1
pve-qemu-kvm: 2.6-1
pve-container: 1.0-71
pve-firewall: 2.0-29
pve-ha-manager: 1.0-33
ksm-control-daemon: not correctly installed
glusterfs-client: 3.5.2-2+deb8u2
lxc-pve: 1.1.5-7
lxcfs: 2.0.0-pve2
cgmanager: 0.39-pve1
criu: 1.6.0-1

Code:
uname -a
Linux server5 4.4.13-2-pve #1 SMP Fri Jul 15 06:36:47 CEST 2016 x86_64 GNU/Linux

Thanks a lot!
 
After hours of trying I'm a bit further: Re-trying http://tj.mk/install-proxmox-4-hetzner-debian/ this tutorial brought at least the effect that I can ping the debian 8 guest and when I try to ssh I get the login prompt. Unfortunately it won't accept the password I entered during the guest creation. I can't use the vnc console within proxmox...
 
And the solution to this is:

The proxmox debian minimal install image has the "PermitRootLogin without-password" option enabled within the bundled sshd_config so you can't just ssh into your freshly new created VM - stupid, eh?!

To change this: On your proxmox host enter ssh - there:

1) pct list

This lists all your created guests.

2) pct enter ###

### is of course the number of your guest. So you're not in your guest and can now for example edit your /etc/ssh/sshd_config regarding this without-password-stuff to "yes".

Later on of course please work with ssh keys and re-set this to without-password for security reasons.

But this as a standard behaviour is imho not very good.
 

About

The Proxmox community has been around for many years and offers help and support for Proxmox VE, Proxmox Backup Server, and Proxmox Mail Gateway.
We think our community is one of the best thanks to people like you!

Get your subscription!

The Proxmox team works very hard to make sure you are running the best software and getting stable updates and security enhancements, as well as quick enterprise support. Tens of thousands of happy customers have a Proxmox subscription. Get yours easily in our online shop.

Buy now!