Re: [Engine-devel] SPICE IP override

Ewoud Kohl van Wijngaarden píše v St 07. 11. 2012 v 12:08 +0100: > On Wed, Nov 07, 2012 at 11:23:27AM +0100, David Jaša wrote: > > Ewoud Kohl van Wijngaarden píše v St 07. 11. 2012 v 11:16 +0100: > > > On Wed, Nov 07, 2012 at 03:52:14AM -0500, Simon Grinberg wrote: > > > > ----- Original Message ----- > > > > > From: "Michal Skrivanek" <michal.skrivanek(a)redhat.com&gt; > > > > > To: engine-devel(a)ovirt.org > > > > > Sent: Tuesday, November 6, 2012 10:39:58 PM > > > > > Subject: [Engine-devel] SPICE IP override > > > > > > > > > > Hi all, > > > > > On behalf of Tomas - please check out the proposal for enhancing our > > > > > SPICE integration to allow to return a custom IP/FQDN instead of the > > > > > host IP address. > > > > > http://wiki.ovirt.org/wiki/Features/Display_Address_Override > > > > > All comments are welcome... > > > > > > > > My 2 cents, > > > > > > > > This works under the assumption that all the users are either outside > > > > of the organization or inside. > > > > But think of some of the following scenarios based on a topology where > > > > users in the main office are inside the corporate network while users > > > > on remote offices / WAN are on a detached different network on the > > > > other side of the NAT / public firewall : > > > > > > > > With current 'per host override' proposal: > > > > 1. Admin from the main office won't be able to access the VM console > > > > 2. No Mixed environment, meaning that you have to have designated > > > > clusters for remote offices users vs main office users - otherwise > > > > connectivity to the console is determined based on scheduler > > > > decision, or may break by live migration. > > > > 3. Based on #2, If I'm a user travelling between offices I'll have to > > > > ask the admin to turn off my VM and move it to internal cluster > > > > before I can reconnect > > > > > > > > My suggestion is to covert this to 'alternative' IP/FQDN sending the > > > > spice client both internal fqdn/ip and the alternative. The spice > > > > client should detect which is available of the two and auto-connect. > > > > > > > > This requires enhancement of the spice client, but still solves all > > > > the issues raised above (actually it solves about 90% of the use cases > > > > I've heard about in the past). > > > > > > > > Another alternative is for the engine to 'guess' or 'elect' which to > > > > use, alternative or main, based on the IP of the client - meaning > > > > admin provides the client ranges for providing internal host address > > > > vs alternative - but this is more complicated compared for the > > > > previous suggestion > > > > > > > > Thoughts? > > > > > > I agree with where you're going with this. The story I'd like to see > > > supported is close to this. We have external customers who should know > > > nothing about our internal network, but should be able to access the > > > console of their VMs. Currently we do this with a custom frontend which > > > uses the API (and is about as old as the RHEV 2.2 API) and a TCP proxy, > > > but we'd like to move to the standard UI. Currently the console > > > connection prevents us from doing so. > > > > You could do that with this proposal, if you: > > 1) DNAT some external-facing IPs to your hypervisor display network IPs > > 2) resolve display network FQDN to the DNATing machine IPs for external > > queries. > > I imagine you need 1 external-facing IP per host, which makes it > expensive to scale since IPv4 space is very limited. That's the cost of quick-to-implement solution. If it is possible to have per-host display port range, you could work this limitation around by setting non-overlapping ranges for each host and use a single proxy or DNAT machine that would decide which port to forward based on the range.