DRAC 5 console with Firefox 3.0.5 on Red Hat

Stroller stroller at stellar.eclipse.co.uk
Wed Mar 17 23:46:22 CDT 2010


On 18 Mar 2010, at 00:24, Adam Nielsen wrote:

>>> I would've preferred to use VNC as it's readily available and easy
>>> to install, so I'm just wondering why Dell chose a custom protocol
>>> instead.
>>
>> Exceedingly good question!
>
> And one I suspect we'll never hear the answer to :-)
>
>> I believe that the original VNC project ceased (with the closure of
>> AT&T Laboratories Cambridge) without encryption as a feature. I have
>> always felt this a shame, as there seems to be some fragmentation of
>> projects now. Some of the original developers formed RealVNC, but  
>> they
>> sell their product and I don't believe the GPL version offers
>> encryption.
>
> There have since been enhancements to the (open) protocol that add
> encryption, and anyone worried about this could just SSH into the DRAC
> and port forward VNC over the secure connection.  This might be fiddly
> to set up if you've never done it before, but still much easier than
> trying to get it working through a browser.

I meant this to kinda address your very good question. ISTM that  
there's been a lot of fragmentation between VNC clients. If AT&T Labs  
hadn't closed at the time they had, maybe they would have released  
fully-open and GPL VNC server and clients. If that had happened,  
surely everyone would have worked off this same codebase. As it was,  
development by 3rd-parties happened at a non-optimal time for  
compatibility of this feature they all needed. I'm not going to get  
into a detailed history or comparison, but I believe there are  
incompatibilities even between the fully-open softwares.

>> One might conjecture that this DRAC incompatibility may be related to
>> this.
>
> It seems funny that they'd put so much effort into the custom plugins
> when (IMHO) it would be far easier to automate the SSH port forward  
> and
> load a free VNC client.

My Blackbox KV9308 KVM offers VNC over ssh port-forwarding. It's  
utterly lush. It even implements a menu displayed inside the VNC  
framebuffer, so that you can switch the KVM to view different managed  
servers (resync the mouse, virtual keyboard, adjust video quality and  
settings) from within the standard VNC client. I'll have to post  
screenshots if anyone is interested.

> Cross-platform support can't be the reason for
> putting it inside a web browser, given the limited platforms it  
> actually
> works on.

Yeah, I know. It's almost clownish. It seems like a classic example of  
enterprise development gone wrong.

The browser plug-ins do offer the virtual-media facilities, but they  
operate on a separate port. So why couldn't the screen viewer (server  
and browser-launched viewer) be completely VNC based?

Dell are not unique in doing this, mind you - my last KVM-IP was just  
the same. Actually, that was rebadged by several companies (including  
Avocent) and the software was based, I believe, on a reference  
implementation by the Tawianese manufacturer of the framegrabber chip.

Like I say, I have to wonder if any kind of encrypted VNC standard or  
well-enough developed open client/server was available at the time  
that the DRAC was first developed. I don't think there was.

Stroller.



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