Maximum number of user for DHCP/DNS services

Hello everyone,
I would like a recommendation for best device for VLANS, DHCP and DNS services for a mini network setup for approximately 150 users. The device will not do wireless, being taking care of by other devices.

DHCP to serve 4 VLANS
and DNS for simple DNS filtering using a blacklist via dnsmasq and DNS request Logs.

somebody suggested me the xiaomi midwifi 3G but to me the part DNS filtering using a blacklist via dnsmasq and DNS request Logs might consume more CPU than what is inside this little device.

By which he stated that dedicated device for such use from other vendors are using same processors with less RAM.

Any suggestion/recommendations from you people are most welcome.

thank you

You probably won't fill up your RAM with "static DHCP leases" (and their corresponding local DNS entries) any time soon (a couple of hundred entries are easy - and before you get into the thousands you'll move to more adequate hardware for other reasons anyways), but DNS based ad filtering pretty much always starts around mid 5 figure ranges of blocked domain, well up into the hundreds of thousands or even millions. That is where RAM becomes a real issue (especially under certain circumstances, like dnsmasq not handling DNS requests originating over tcp very well), 128 MB RAM can easily be filled up by that, even 512 MB might be.


To be clear, you have 150 wired workstations connected simultaneously?

You will need some serious horsepower for such a network, this is definitely x86 territory. What is the uplink speed? Will most of the traffic stay on the LAN between the workstations, or is it mostly going out to the internet?

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wireless devices from various AP serving guest, 1 gig uplink to internet, the traffic will go online with 2 mb throttle per device via wireless controller

Ah, that makes more sense. I (before coffee, that's my excuse!) got a picture in my mind of a small office. This sounds like a conference center setup...

I'd still be tempted to put in a big-horsepower router (x86), as you probably want good SQM on it to manage all those streams and reduce bufferbloat (thus making your guests much happier). A couple hundred dollars for a router is probably going to pale in comparison to the cost of all the WAPs.

Here's a comment I made last week about a Aliexpress "mini-PC" that I got last year, it may or may not be of interest to you:

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With 1 GBit/s uplink, inter-VLAN-routing and 150+ concurrent clients, x86_64 does make (a lot of) sense.


this seems very interesting :

That would work, but it's even more overkill than the Atom/Celeron boxes I usually overkill with... Unless you're doing some really intense DPI (deep packet inspection, Snort, Suricata, et cetera) and SQM, you are unlikely to need to spend that kind of money for processing. I'd be inclined to get one of the cheaper Protectli/Topton-like boxes that have more NICs and less CPU/GPU/RAM.

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