2021-10-15

Mitsubishi Lossnay+GUG aircon (not actually working)

We have a bit of a mystery here - the brand new, expensive, ducted air-con in the house does not work!

So what does not work exactly?

Not actually able to cool a room!

The biggest issue is it cannot cool a room - not even close. (It can't heat one much either)

This is a temperature plot for my study, 3m x 3m, you don't get a lot smaller than that in terms of a room to air-con. A=Portable unit on, B=Portable unit off, C=Start two hour cool only full fan test.

The test was with the other room vent closed so the unit was only cooling one room, in to a closed empty room, no heating on anywhere in the house, and outside temp of 19C. Not a challenge for any air-con really, and as you can see, the cheap portable unit managed with no problem (even with the door open most of the day). And yes, the fan speed control does work, and was on full.

I expected at point C the room to cool at least as fast as the cheap portable unit. What happened is it just about managed 0.8C in two hours! It was blowing cold air (measured at 9C) but not as lot...

The fix - well, the unit only has a 100mm vent in to the room. This seems small I must admit, and at full fan like this it is noisy. So they are changing to a 150mm vents today...

Did it work? In short, no. The bigger vents are quieter, which is nice, but the same tests showed maybe 1.5C drop and bottoming out just below 21C after more than an hour. Compare these big 3.5kW systems to a much cheaper 1.5kW portable unit which is able to drop my study (and hall way as door was open) from 23C to 18C in 15 minutes. With the door open the new air-con cannot cool my room at all!

This is now waiting on Mitsubishi to explain and fix. I won't say who the installers yet as they have been pretty good. Let's give them the chance to get Mitsubishi to fix it all.

But how is this even possible?

The issue for me here is that they sell this system, even with the smaller 2x 100mm outflow vents. So forgetting, for a moment, whether the suppliers got it wrong for the rooms we are trying to cool (two rooms each unit, one of which is much bigger than this 3m x 3m study), we have the issue that this whole unit running at full cooling and full fan cannot cool a 3m x 3m room.

So what the hell is the this unit for - what size room are they expecting it to be used with, ever?

The change to 150mm vents actually meant them cutting out the larger holes as the cowl as it is only supplied with the 100mm outlets.

This leads me to think something else is wrong, but we have no idea what. How could this ever work anywhere?

Cannot set temperature!

The controller has options - either "return air" temperature measured at the lossnay unit, or the room temperature at the controller. The controller has a sensor in it. Given that we have two rooms per unit, we are using the temperature at the controller (which is not in the room with the return in it). This is all as per the manual.

Only it does not work! Cooling the room down to 19C (using the portable unit, obviously), it showed 24C. Indeed, it even went up from 23C while we did this. Using freezer spray actually on its sensor does nothing, still 24C. No clue where it is measuring but it is not in the room - we even tried putting hot air in the room that has the return air flow but that did not make it go up at all.

The fix: Well, again, waiting on Mitsubishi.

Watch this space.

2021-10-08

New Mitsubishi Ducted Air-con with Lossnay (bad user interface)

As some of you will know, I have moved to sunny Wales. My new home did not have air-con so I am finally having that installed. I have gone for a ducted system this time (yes, more expensive) as it allows simple vents in the ceiling rather than a large indoor unit in the rooms, and it should be quieter. However, the main reason is that we now live on a main road, so cannot really open windows to any of the bedrooms - the ducted system I have gone for has a "lossnay" which provides fresh air as well, and saves us having to open windows. More on the actual aircon later, this post is just about the quite unbelievably bad user interface.

For a start this is an "industrial" air-con, which sadly means it is a simple wired controller and not WiFi, or anything useful like that - do not be surprised to find a "reverse engineering Mitsubishi air-con controllers" in a future blog post :-)

The air-con is three parts, an outdoor unit, and indoor unit (GUG) which does the cooling/heating, and a lossnay which does the fresh air (filtering and heat exchange). This is in the loft...

The lossnay is on the left and the GUG is on the right. To be clear, the GUG is designed to work with a lossnay, it cannot work without one as it has no fans of its own. I think the lossnay could be used for fresh air without a GUG though.

Controller

The controller is not too bad, it has a dot matrix LCD and buttons. It is newer than some where they have fixed icons on LCD. It has the obvious controls: mode, temperature, and fan speed. Good.

But, no. The fan speed says "unsupported function" if you try and change it. You need to have a separate "lossnay controller", which basically just lets you set the fan speed.

But there is a 4 wire link cable between the lossnay and GUG, what the hell is that used for? Well, all I can see is that it means is it turns off the lossnay when turning off the GUG. Remember the GUG can only be used with a lossnay attached, this is not some obscure optional extra.

We (myself and the installer) found the setting to tell the GUG it has a lossnay connected (but this unit cannot work without one so why is there even a setting?!), and it shows a nice icon indicating it has a lossnay. But still does not let you control the lossnay from it. Why? Also, the icon looks like it shows the "mode" the lossnay is in (yes, it seems to have a non heat exchange mode, which is pointless) and fan speed, but in fact the icon does not change to actually show the mode or fan speed. How shit is the UI?

Apparently you can run the lossnay without a controller, and the GUG will turn on/off at full fan speed, which is not that useful.

Of course, this also means you cannot run the fan in an auto mode as the lossnay does not know what the GUG is doing. So you cannot have full fan to get to temperature and quiet fan to maintain temperature.

Oh, and crossed zeros. A pet hate of mine. This is not a hand written COBOL coding sheet in the '70s, it is a temperature display. Why make it look like 28℃ not 20℃ to anyone with poor eyesight?

Another gem is that you can turn the temperature down to 12℃, nice, but then it snaps back to 19℃. Why 19℃, that is way higher than I have seen on other air-cons - it will probably do as I would rarely want it that cold. But still, why? And why allow setting below that if it cannot be set lower? Just stupid UI again!

Another thing that seems odd is that the controllers are identical. Same display, and buttons. Looks like identical hardware. The lossnay controller even has a thermometer in it even though it does not need it. But they must have different firmware as they cannot be swapped around. I would have made one controller and made it generic to work anything, but no, they are different!

2021-09-23

A use for the keypad

The Solar System alarm that I have created does work with a standard Honeywell Galaxy Mk7 keypad/display module.

However, until now, I have not really managed to work out a good use for how the keypad can be part of the system. But I have been working on that.

We now have clear display of inputs that trigger alarm, or inhibit setting, or faults, or tampers. We have setting the alarm, and unsetting using a PIN. Yay!

The way it all works is down to a small PCB, designed to fit inside the case of the display. It works off the same 12V supply, and provides RS485 to the keypad/display.








2021-09-04

Shelly1 on 12V

I have used Shelly1 for a while, and have loads of them in use.

One of the nice features is they can run from 12V. Well, actually, they can run from mains, 24V-60V DC, 12V DC, or (via connector pins) 3.3V DC. You move a link for 12V working. Pretty versatile.

I have used them in the house here on my door bell circuit which runs from a standard alarm system 12V battery box. All fine.

I planned to use with an alarm system as well, running from the 12V battery box. First two were fine, but then the next did not work. I tried another and it also did not work.

I did some googling and people report that the 12V is meant to be exactly 12V. I must ask Shelly to confirm really, but the comments were 12V and not a battery (which is 13.8V). My example use was actually 14V. It would be a pain if it could not run from a standard 12V battery box.

Well, pushed for time, I found some 12V LDO linear regulators and got for next day. Oddly when installing these to give an exact 12V clean DC for the Shelly, the ones that were not working still did not work?!? I tried yet more, and they did work.

What is even weirder is one that was working off 14V did not work off 12V, so I had to find another. It is a good job I had 20 of them.

So it seems the 12V working, is, err, fussy, and inconsistent.

Anyone else seen this?

What a week!

This has been a hell of a week, and far more actual hard work than I am used too, and after it all (averaging over 15k steps a day) I have not even lost any weight!

The plan was simple, replace existing 7 door system, and PIRs and exit contacts, and so on. 28 modules in total. I have carefully made and tested all the modules and spares. All ready to go.

But I ended up making work for myself by tidying the wiring. The new system just needs power, so ended up with 6 battery boxes, and removing the old power and bus wiring. Much neater. I also needed to change the exits from rangers (that were unreliable) to new exit buttons, and hence also needed to change the break-glass boxes as they were integral. And I wanted to move the break-glasses further from the letter box (for obvious reasons). This meant running wires down the aluminium door frames on the front doors (to be tidy), which is easier said than door. I probably wasted a day on that (and I had some help). I can recommend NYLON CABLE & FLEX DRAW TAPE 30M (98FT) (screwfix 75807) for the job :-)

Finding the cable runs to bell boxes was also fun, and I gave up chasing wires to original PIR and door sensors and just ran new cables. Ceiling tiles for the win.

We actually have a mystery - the original alarm when we moved in was removed something like a decade ago, but the PIRs were still in place. When the new galaxy alarm was installed new PIRs were put in. I have actually put in new PIRs this time with integral ESP32 WiFi modules in the PIR. Part of the work was removing the galaxy system which replaced have already replaced what was there before, and removing all the old battery boxes. The original PIRs still have power and blink when people move? But there are *NO* battery boxes nor alarm panels in the building at all. I have literally removed them all, and the new battery boxes only go to my new kit. So WTAF. If I had time I'd have investigated further, but it is a mystery!

The result is it took a whole week, and I have to admit I was losing my enthusiasm somewhat during the week.

What did not help is finding some bugs and issues. I expected some, and a couple of small snags were simple, but the biggest issue was the wifi mesh being unstable. It was fine at the start but got worse during the week. I found issues with multiple wifi channels (2.4GHz) which I fixed with config changes on the APs. But I would find the mesh unstable. Reseting the wifi could fix, but not always, and changes to wifi config helped, but not in a concrete way. I wasted a lot of time on that. But ploughed on with the installed.

But Friday it was clear the problem was now intractable - the modules were all resetting every 30 seconds or so. The nice thing is the system was still usable. People in the office could come and go, as it resets very quickly and works autonomously. But it cannot work as an alarm if the mesh is not working.

It seems (and I have to do a lot more bench test and investigation to be sure) that the modules may be running out of memory when the mesh gets beyond around 12 units. This is very disappointing as I I can't see why the mesh would need much memory at all - each routing entry is a 6 byte MAC and very little else. It will be interesting to investigate.

Thankfully the site is two distinct adjacent units, so the fix was to make it two sites. That is a pain, as it means provisioning fobs for two sites, and if someone had not mistakenly ordered only 2k DESFire fobs, that would be easy, so new fobs were programmed, again! Just means slightly more admin. I cut down the sites slightly and ended with both sides with 12 units. When one had 13 it was not quite stable, but 12 seems fine. So we have a work around.

It may be that in longer term we need some modules using ESPs with extra RAM to act as root nodes, something to consider if I cannot track down the memory footprint problem.

Even so, the end result seems really good. Time will tell.

P.S. I have improved stability a lot with some tweaks to the way we work the mesh, but not solved the underlying issue. I suspect big step will be waiting for mesh code in ESP IDF to mature a little. Like cheese.

2021-08-29

Solar System goes live

As I have said, I have been working on a number of boards as part of a project that provides access control and alarm functions in a modular way: https://github.com/revk/SolarSystem

I have test systems on my bench, and I now have a small system at home. It is all working well and has helped me iron out some of the bugs.

But this week is the first proper system with 28 live WiFi nodes, meshed, and linked to the back-end cloud control. Scary stuff. It has bell boxes, keypads, PIRs, reed switches on doors, fire alarm inputs, even a panic button in a disabled toilet. Importantly it has a lot of doors. The design is pretty robust, and the whole project is all open source.

My case is packed, and boxes of tools and parts are all ready. It was a lot of work making all the modules. A lot of time with a steady hand with tweezers. I even have half a dozen spares, just in case.

So the night before I head off to start the install, I have imposter syndrome kicking in. How did I think I could possibly design and make a complete access control and alarm system from scratch (PCBs and s/w)? Well, seriously, I need to give myself a kick - I have been doing this shit long enough to know this is bullshit. It will be fine.

Assuming all is well (and I know there will be teething problems, bugs, and features, all of which will need addressing), my next big challenge is whether I can progress this in to a proper product to sell. At the very least, to make the modules (as pictured above) something we can legally sell.

In the mean time, other hackspaces that are interested, do get in touch, and I can help you set up such a system.

2021-08-28

NHS covid pass

I decided to check how I get an NHS COVID19 pass / QR code.

Update: Thanks to all that pointed out the couple of subtle clues on how to get an NHS login, which I missed initially.

I googled, and it seems you can ask for a letter or get it digitally, cool. But you need an "NHS login".

Well, I don't know what an NHS login is, but there is this helpful site, https://help.login.nhs.uk which tells you all about it. Nice.

This looks comprehensive. But I don't have an "NHS login", so let's try the "How to set up [an] NHS login"... https://help.login.nhs.uk/setupnhslogin/


OK, we have "What is NHS login" and "What you need to set up an NHS login" (yes, an "an" this time). There are other pages with more information on how to prove who you are, etc. There is the "Where can you use NHS login". OK, good.

Update: For those saying "just use the NHS app", I'm in Wales now, and it does not work!

Update: Oooh, it says clicking the button lets you create a login there, missed that the first time, but the the actual login page does not say that.

But call me thick, and maybe I am being blind here, but where is the "Register for an NHS login" or "Create an NHS login" link or "how to" on that? I looked around and cannot find it. It does not seem to actually tell you "How to set up NHS login" at all, missing that one crucial step of how you start the process!

I kept looking and I found the NHS COVID pass page, https://covid-status.service.nhsx.nhs.uk which has a login link.

Nothing about registering or creating an NHS login on there either. What am I missing.

Well, on a whim, I clicked on the "Continue with NHS login" link, even though I don't have one. Is continuing with NHS login when I don't have one "hacking"? A breach of The Computer Misuse Act 1990 maybe? You then get a login page...

Well, I don't have an "NHS login". What I did not spot initially was the "If you do not have an NHS login" bit. This seems to be the first clue that maybe I can make one if I enter my email address anyway. Why is this hidden away behind a "Continue with NHS login" link?

So now I get the option to "Set up a new NHS login". This is what I had been looking for all along. How the hell is this not on the the help site, or, well, anywhere before you actually try and "login"?

Update: One page for COVID19 Pass does say "You will need an NHS login to use these services. You'll be asked to create one if you do not have an NHS login already" but the page you then go to does not say that, just "continue with NHS login".

Anyway, I continued to create an NHS login. You go on through a few info pages, and create a password, and then this error...

Well, that is helpful. Giving that the previous page was password selection, and I used the browsers password manager to make a "secure" password, I naturally assume it is as password issue. So I try entering a password manually. I tried several passwords, simpler and simpler, and no joy. It simply would not work.

Then, on a whim, I tried a different email address. Just to be clear, that first page does do some validation on email addresses, e.g. ...

So I really had no reason to expect that it was unhappy with my valid email address. But indeed, using a different email address, it actually allowed me to proceed beyond the password set up. I have emailed them asking that they correct my email address, obviously.

When it came to mobile checking, I decided to use an 07 number, rather than trying 01 number, as clearly it is a stupid web site.

The domestic (48 hour!) QR code does not need any more than name, DOB, NHS number. The other longer pass needs ID image and a video and I'm waiting for that to be confirmed now. However, having seen someone else's, I note that the document says this...

OK, so it has an expiry, but how exactly does that expiry "protect you data privacy". The barcode does not fade after 30 days. The "data" is still in the expired barcode, and can still be read. So how exactly does the expiry protection anything - how does it do any more than cause inconvenience for the user?

Indeed, I am told if you request a COVID letter, there is no expiry - so do they not care about your data privacy when sending a letter, or was that just a lie? Having an expiry actually makes "data privacy" worse - if you printed the QR code, you will have to dispose of that securely somehow every time it expires. Why not just be honest?

And finally... The Welsh site https://gov.wales/nhs-covid-pass-prove-your-vaccination-status says :-

But the "domestic" QR code it gives you says ...

So how do I get a QR code valid in Wales?

2021-08-05

Review how emergency services handle location data from the public.

I found an interesting web site which does rather highlight some of the issues with what 3 words, w3w.me.ss. Well worth a look.

Sign the petition!

Whilst it is a fun application, a novelty, I personally do not feel it has any place being promoted by emergency services. And this post is my honestly held personal opinion, as always.

If they want to "handle" w3w addresses from the public, that may make some sense, as it is popular. If the app if given to them free of charge (as seems to be the case), and if they take any w3w address with some caution, checking the location by other means if possible, then yes, fine.

But reports on social media (including from people I personally know) suggest that w3w is not just "promoted" by emergency services but actively preferred to the extent that call handles will refuse to take simple o/s grid references and insist on a w3w address. For one recent case, the police force in question confirmed that they should have taken an o/s grid reference. But in practice this seems not to be the case.

What seems worse is stories of people being talked through downloading the app on an emergency call. This is quite incomprehensible. Even if you want a w3w address for some reason, it is far quicker to send someone to the w3w web page (what3words.com) which shows your location. The only possible reason to download the app is so the user has the app on their phone. It is a purely marketing activity, as someone is more likely to use w3w if they have the app. Do we really want emergency services actively engaged in time consuming marketing activity for third party closed commercial apps, during an emergency call?

As I say, much of this is anecdotal, but social media is full of this, as highlighted by w3w.me.ss.

What is especially odd is that w3w's own terms and conditions are not consistent with use in an emergency. They expect you to read, understand, and agree many thousands of words before use, and expect you to check the terms before every use. This is not sensible for the caller, and the emergency call handling staff, to do in an emergency situation where time is critical. Also, the terms prohibit use where it could lead to someone dying, which is often the case in an emergency. Given these clear terms, it makes no sense emergency services would even be considering w3w usage, let alone promoting it. It is almost as if they did no checks at all on how it works or even just reading the terms.

There are ways to get location from callers, not just (long standing, open standard) alternatives like o/s grid references or even simple latitude/longitude, but means that don't involve any reading out, like SARLOC or AML. These should be available to emergency services. Even if there is need for a caller to give a different location, knowing where the caller is puts that in context and helps eliminate errors, whatever format is used.

So, in order to try and address this, I have made a petition. It calls for "Review how emergency services handle location data from the public." which I think is fair.

Sign here! And do share the link to get some traction, if you agree this needs reviewing. Of course, if you feel strongly enough, it is also worth contacting your MP over this.

2021-07-31

[non] changes to Highway Code rule 170

There is a lot of talk of changes to the Highway Code that are happening, notable rule 170.

Some motorists are really cross at the "new rule". There is always some bad feeling between cyclists and motorists, but this is especially odd, as the "change" is not really a change at all. So the only people cross over it are those that clearly have no clue the rule already exists.

How is it not a change?

The existing rule says "watch out for cyclists, motorcyclists, powered wheelchairs/mobility scooters and pedestrians as they are not always easy to see" so motorists already have to be on the look out for pedestrians when at side roads.

It also says "watch out for pedestrians crossing a road into which you are turning. If they have started to cross they have priority, so give way". It makes it very clear a pedestrian crossing a side road has priority.

The "new rule" only makes a very tiny change to this, as it requires motorists to give way to pedestrians "about to cross the road".

But it is hard to see how that is not, in effect, already the rule. Motorists already have to watch out for pedestrians, and a pedestrian can change from "about to cross the road" to "crossing the road" in a tiny fraction of a second by putting their foot out. I mean, this can happen far quicker than a car getting to the pedestrian, so the motorist (watching out for pedestrians) has to allow for that happening and be prepared to give way to the pedestrian crossing the road at a moments notice. It is hard to see how this is different to the new rule. So in that respect the rule has not really changed. The only other aspect of this change is from the pedestrian point of view where they may feel empowered to cross a side road rather than wait for a car - but, as always, pedestrians have to be on the look out for motorists unaware of, or ignoring, the rules.

All of the back-lash I have seen on this ignores the fact that pedestrians crossing a side road ALREADY HAVE PRIORITY over vehicles turning in to the side road.

The Highway code even has an image showing a pedestrian that would not see the car is planning to turn (even if they looked a moment before), which is, I am sure, why the rule exists.

Publicity

It is obvious from the posts on social media that a lot of motorists have no clue about rule 170. I also see this every day as I cross a side road on my walk. The typical scenario is a car, STATIONARY on the main road, waiting for traffic the other way, and I start to cross the side road. The car then expects me to stop in the middle of the road to let them turn in to the side road because of a gap in the motor traffic. I don't try to get run over, but I do make it clear that, obviously (as per the Highway Code), I am not expecting to stop. This has led to enough drivers getting cross (apparently they never read the Highway Code) that I even have cards with rule 170 printed on them to hand out.

So this non-change to the rules makes no difference on its own. What will make a difference is all the publicity it generates. Hopefully it will make drivers aware of the rule that has always existed, and the somewhat cosmetic change to that rule, and they can start giving way to pedestrians at side roads as they always should have.

Anomalies...

I do hope they clear up two anomalies I have noticed in the rules though...

  • Pedestrians crossing the side road have clear priority over vehicles turning in to the side road, but I don't see anything saying they have priority over vehicles leaving the side road. So in effect they have priority over half the road. This seems like a mistake, and maybe there is some other bit of the highway code that even I have missed that says this. It would be nice to make the priority apply for the whole width of the road.
  • The priority is over vehicles "turning" in to the side road - but what of a cross roads or a side road on a bend where no "turning" is needed. As written, the rule does not apply in that case. I hope the new rule makes that clearer, maybe using "entering" the side road, or "entering or existing" (as above).
  • It is not entirely clear if the rule covers things that may not really be a "side road", such as an entrance to a private car park, etc. I assume they are a "side road", but are they? I am not sure, so maybe the new rules could make that clear too.

2021-07-26

Fun with DHCP

We have had a slight issue at the house here, we have some Apple HomePod things. My son decided to put several in the house when staying here and now my wife is using one.

The snag is that they keep falling off the internet! A power cycle fixes, but it is very frustrating.

I have found the solution though, and I think it points a finger at the cause.

And it is all down to DHCP. Yep, not DNS this time. Not IPv6 even. DHCP!

So what's the problem?

First off, what's the kit?

  • FireBrick doing DHCP and Internet gateway
  • Aruba APs
  • Apple HomePods

The failure did not seem to be all the time, but could be. Sandra has almost given up using them as they never work. But it seems it can usually renew its DHCP without problems, but sometimes it gets stuck. The logs on the FireBrick showed we kept sending a DHCP "Offer" to the HomePo, but it keeps asking.

I added lots of debug, and confirmed that the request being sent, the DHCP "Discover", does not request a broadcast reply, which is fine, so we send the reply to the MAC of the HomePod and its "new" IP address. This is normal.

On a whim, I decided to try fudging the code to treat the discovery as if it has asked for a broadcast reply. This then meant a Discover, Offer, Request, and Ack - but the HomePod did not see the Ack and so kept asking. I then forced the broadcast on the Ack as well, and bingo, it worked. So the issue is the broadcast used for Offer and Ack.

This is a massive clue.

So more investigating.

The RFC says the broadcast request is in the left most bit of a 16 bit flag field.

PLEASE DO NOT DO SPECIFICATIONS LIKE THIS!

I fully understand that bits in a byte may be sent "on the wire" low or high bit first, or high to low bit first. I fully understand that bytes in a word may be ordered big endian or little endian. The above diagram is for a 16 bit "network byte order" value (i.e. big endian).

They number the bits from 0 to 15. Actually they number the gaps between the bits 0 to 15.

In my view there is only one way you should number bits - by their binary power of two value. I would always write that in the way we write numbers, most significant first, so would write that as bits 15 to 0, and it is bit 15 that is the B flag. I don't mind if showing as bits 15 to 8, and 7 to 0 (big endian) or even as 7 to 0, 15 to 8 (little endian), but number each bit by its power of two value, please!

Some people number as order on the wire, starting from 1. So 1 to 8 may be 0 to 7 or 7 to 0, who knows! Please do not do that. But at least if numbering bits 1 to 8, you have some clue that something is wrong.

So, to be quite frank, I actually do not know if this is bit 0 or 15 in a network byte order (big endian) 2 byte (16 bit) value. We assumed it is bit 15, i.e. bit 7 in the first byte. But seriously, from bits numbered 0 to 15 and a reference to "left most bit" I don't actually know for sure. I started to doubt we had read the RFC correctly!

Thankfully empirical testing shows the flags as 0x8000 from other devices, so either it is bit 7 of first byte, or other devices have the same fun reading the RFC. 

So who is at fault here?

Well, my son has the same FireBrick and the same HomePods, but different APs. That all works. That is another clue.

My Aruba APs are set up to inject data in the DHCP, which is good. I get details of the AP and SSID, and can even tell the FireBrick to allocate based on SSID even if different SSIDs on the same physical network. All good.

It may be that it is stripping the broadcast bit, bit that does not explain why it works after a power cycle. Interestingly the working DHCP renewals did not have the injected AP details, it seems. This points further to the AP being "special"

My son does have different network switches as well, so it is just remotely possible that it is a switch level issue, but that seems unlikely - the DHCP discovers are from the right MAC so all switch learning should be fine.

P.S. Yes, I had changed the filtering to disabled already.

The work around...

FireBricks now have an option to force broadcast reply. And it works. Alpha out soon.