It seems to me that the bulk of the market for a PiHole is as an appliance. Enthusiasts can get one up and running fairly quickly, at a low cost, and not have to mess too much with other devices in their environment.

Running it as a VM has obvious attractions but there are some drawbacks:

- must leave the host running, which may be less reliable than a hardware Pi and use more electricity
- PiHole VM can only serve devices on it subnet, or downstream
- it's probably easier to reconfigure an environment with it running as an appliance. If it's a VM on a host, there may be other limitations on how that host can be configured - and therefore guest VMs

Your post is not that cryptic, covers the main points pretty well. As you point out, for PiHole to be useful at all running as a VM, networking must be bridged in VirtualBox. This basically turns off NAT so the guest is on the same subnet as the host. You can set up a static IP reservation on the DHCP server based on the PiHole's virtual MAC address. Annoyingly, when you do that with some older Windows Server OSs you get event log warnings that the server doesn't have a static IP address, I imagine Linux is smarter than that.

Speaking of cable chaos, I'm beginning to think that for typical small business environments where security is not paramount, that routers with actual routing capability are a good alternative to cascaded consumer-grade routers. Something like the Ubiquiti ER-X (about C$90) can be used to set up multiple isolated subnets. The good folks at Gibson Research have put out a paper about configuring one that way: https://www.grc.com/sn/files/ubiquiti_home_network.pdf

Most consumer routers have security holes, which are not usually patched after a relatively short support period. Ubiquiti is business class and has ongoing support/firmware updates. The ER-X in particular is about 4 years old and relatively stable. How good is subnet isolation within a single device like an ER-X compared to cascaded consumer routers - I don't know. But I'm guessing reliability of software and hardware in 1 business class device is better than multiple consumer grade ones.

Another issue I'm starting to see is that some business and home office networks are getting ISP service that consumer grade routers can't handle i.e. when plans offer 150Mbps, 300Mbps or higher. There's a better chance that a business class device can keep up e.g. https://community.ui.com/questions/ERX-linespeed-performance-with-Hardware-offloading/f55fca84-25aa-472f-8eda-16a2db4b7936

Overall, I'm quite impressed by the capabilities of the Ubiquiti ER-X at its price point.

As for YouTube ads, for a while now I've been using the "Enhancer for YouTube" add-on for FireFox. I've never - not once - seen an ad that was not part of the content itself. Videos start up without delay and there are no breaks or stutters where ads would normally appear in the middle of the playback. Very highly recommended. https://www.mrfdev.com/enhancer-for-youtube . It's very easy to enable or disable the add-on, so you can have it active only when you're on YouTube if you're concerned it might be spying on you. With the Enhancer the YouTube experience is so improved, that if you ever have to watch a video without it, the experience is distasteful.

Interestingly, the PiHole uses underlying technology that can be used for good or bad. In the black hat world, DNS poisoning or man-in-the-middle attacks are serious threats. The PiHole uses the same idea for good (as long as you're not an advertiser ;)) Similarly, advanced malware and anti-virus software are technically the same thing, just used for different purposes.

>>I think the video discusses using a Pi Zero v1.3, which is older kit but still available for $5. The newer Pi Zero W which includes WiFi and Bluetooth is $10. Of course, you need to add a power supply, case, MicroSD card and Ethernet cable so it ends up being a bit more than $5 ;) but most vendors have cost-effective kits to get you going.
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>Read up yesterday night on different Raspi versions - as I prefer cable based LAN where possible, it was reccommended to buy a Pi3 after quickscannng a few reports, although even Pi B is reported to shoulder the load (with disabled logging at least...)
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>While not totally adverse to buying more HW, this would add to the cable chaos around the routers on physical desktop. As I have flooded myself with VMs last week I decided to test waters with software alone. There is a .iso for RasPi, so I spun up Virtualbox and after only 1 hasty install I had thought enough about the issues to get tweaked second approach working. Have now a RasPi VM intercepting the all DNS lookup in my personal/work subnet - with Raspi in HW I could point 2 other routers to the cleaning DNS server. At least for most of my personal electronic zoo I can test it - and the excepted media subnet is not really plagued by advertising.
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>Basic ingredient was switching network from NAT to Bridged in VirtualBox setup, which leads to VM getting IP not from host, but asking router. There you have the same step as with physical RasPi to ascertain fixed IP based on MAC adress, as DHCP might lead to errors on fixed DNS server setting. On second try I succeded in doing everything without mistake. Creating VM, setting up RasPi inside, installing PiHole and re-pointing Router took a bit more than 30 minutes, but not even 5 minutes of concentrated keyboard input. Best done when you are busy doing other things, but really nothing hard - Linux install scripts are great nowadays.
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>Does work - but filters less than expected from video linked in OP, perhaps there are not typical enough german advertising sites blacklisted. Youtube still sneaks some advertizing, not many english speaking sites tested - I am hoping for more traditional "newspaper" sites to load without all that advertizing slowing down my poor old Snapdragons...
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>Currently 25% of DNS queries filtered into oblivion. Will try out next month with it - and then decide if I plunk down ~60-80€ and go with HW RasPi 3 or 4, get a bit more RAM for about same amount or abandon Pi Hole again. Had hoped for better HTML load times with my aging Nexi 7 (only tablets offering Qi loading...), but DNS lookup cache or discard did not really make big difference when checking without direct comparison. I will compare same sites Pi-Holed in one machine, loaded normally via different WLan in the other later to get true comparison not based on memory.
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>If someone wants to follow up with VirtualBox approach but needs better description, ask and I'll type something less cryptic up ;-)
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>thx again for the original link
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>thomas
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>>Most of the manual network settings in the video were because they were testing it on a portion of an already established production network, which they didn't want to disrupt. At one point they did touch on setting routers to dole out the PiHole as the DNS server for any DHCP client. As you point out, that makes it transparent and mostly ubiquitous.
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>>>Interesting usage... I am for the first time actually tempted to buy 1 or 2 to Pi (plural would have been too sweet...) to play when nights are longer again. I did not look / listen to the chip description closely (other than being 5$, which would point to Pi1 ?