[Engine-devel] SPICE IP override

[Itamar Heim]

On 11/11/2012 11:45 AM, Yaniv Kaul wrote:
> On 11/07/2012 10:52 AM, Simon Grinberg wrote:
>>
>> ----- Original Message -----
>>> From: "Michal Skrivanek"<michal.skrivanek at redhat.com>
>>> To:engine-devel at 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?
>
> Lets not re-invent the wheel. This problem has been pondered before and
> solved[1], for all scenarios:
> internal clients connecting to internal resources;
> internal clients connecting to external resources, without the need for
> any intermediate assistance
> external clients connecting to internal resources, with the need for
> intermediate assistance.
> VPN clients connecting to internal resources, with or without an
> internal IP.
>
> Any other solution you'll try to come up with will bring you back to
> this standard, well known (along with its faults) method.
>
> The browser client will use PAC to determine how to connect to the hosts
> and will deliver this to the client. It's also a good path towards real
> proxy support for Spice.
> (Regardless, we still need to deal with the Spice protocol's migration
> command of course).
>
>
> [1] http://en.wikipedia.org/wiki/Proxy_auto-config

so instead of a spice proxy fqdn field, we should just allow user to 
specify a pac file which resides under something like 
/etc/ovirt/engine/pac...?