DHCP leaking with Dante control bridge disabled

[jamesremuscat]

We’ve recently installed a pair of SQ-6es with Dante cards into our existing Dante network, along with a pair of DT168s. The Dante network is set to autoconfigure with link-local addresses, and is separate from our house network that uses DHCP and the 10.x.x.x IP range.

Shortly after adding the SQ-6es, we started to experience some Dante devices dropping off the network (or so it seemed) and being unable to communicate with the other devices. Inspecting in Dante Controller showed that they’d somehow picked up 10.x.x.x addresses from our DHCP server. Of course I double-checked the setting for “control network bridge” on both desks, and it’s turned off as intended. I’ve unplugged both desks from our control network and, since doing that, we’ve not had any DHCP leaks (that I’ve noticed) – but it’s a shame to therefore not be able to use SQ MixPad.

Has anyone else noticed this? Is it a known issue, or a new one – or am I imagining things? I’m running latest firmware for the desks and SQ-Dante cards.

[KeithJ A&H]

@jamesremuscat

This is not something we’re aware of, but presuming there is no other shared part of the network (such as switches or computers connected to both networks) it certainly sounds like something we’d want to look into with you to be sure there is definitely not something happening in the console.
Therefore please contact us using support.allen-heath.com with a little more info on how everything is physically connected and configured.

Thanks!
Keith.

[tourtelot]

Please keep this thread open as the trouble-shooting goes forward. This is really important information for those of us running more and more complex Dante networks that include SQ desks.

For me, I run my controllers, including MixPad, on a separate VLAN connected to it’s own WIFI access point. This along with controllers for remote preamps, JoeCo controller, and CCTV. My Dante server, serving DHCP to the Dante VLAN has never failed and has never been swamped by the DHCP server for the controller VLAN.

I would be very interested in seeing a resolution to your problem.

D.

[jamesremuscat]

Thanks for the replies; I’ll try and find the time to do some proper investigation, and update here / open a support ticket with my findings.

[jamesremuscat]

Good(ish) news, in that I think I’ve identified the source of the problem: There’s a window of about 4 seconds during the SQ-6 boot process in which all traffic from the “network” socket is leaked to the Dante network (at least to the primary). If there happen to be any DHCP requests in that time, then devices on the Dante network can end up with IP addresses from the control network.

I’ve updated my support ticket with this information and a packet capture demonstrating leaked traffic.

[KeithJ A&H]

@jamesremuscat –

Thanks for working with us on this and for updating the post for anybody else who may run into something similar.
We’ll be looking into it further and although it won’t cause an issue in the majority of cases, it obviously has in yours and will be noted as a bug.

Cheers,
Keith.

[jamesremuscat]

Final update from the support ticket: A&H have agreed this is a bug, and the R&D team will need to investigate to see if it’s possible to resolve it with a future software update.

Our workaround for the time being is making sure that the control network is unplugged until after the desk has been powered on…

[tourtelot]

Thanks for this information. Could be important in my rig.

D.

[Tubbs]

I’ve had exactly the same problem on our Avantis. I’ll open a support ticket too.

[Smo]

Has this been resolved on the SQ series? I bit anxious about putting it on a corporate network with this issue?

[SteffenR]

To avoid this, you can still use fixed IP settings for the Dante devices.

[Author]

Posts