With MikroTik CRS804 and MikroTik CRS812 out of stock/ on back order through Dec 2026/ Jan 2027 what other switch options are being considered before jumping into the 5-figure / ‘may be too noisy for home lab’ investment bracket?
How many dgx units?
switchless is an option.
Currently 4 Sparks with preference to avoid daisy chain / PAIR connected topology
I see inventory in Europe, at least, for the MikroTik units.
I have experience with 3x switchess. They can be pretty fast. Some reports online show a performance gain relative to switched - not to mention the lack of airplane noises, space concerns, heat, and the configuration headaches.
I have heard of successes with 4x switchless as well, though I image that may experience performance penalty for the further side of the ring - but you probably know that part by now :).
I like the MikroTik CRS804 because I can cluster up to 8 Sparks using 400G DAC QSFP-DD to 2x200G QSFP56 Y-branched cable so for the investment to your point 3X CRS804 can support a 20-Node cluster with power and temperature needs sure at a fraction of the 24-port 400G/200G switch rates. It’s a shame supply chain hit a drought this fast.
What are you managing on your 3 switches, if you don’t mind me asking? :)
you’re really planning big!
You might be better off with some of the enterprise gear at that point. Maybe check Ebay for some corporate fire sales?
Maybe an Nvidia Mellanox MQM8790-HS2F on the high end or a surplus dell powerswitch?
I don’t know much about the different port specifications though. I’m not sure if there’s a difference between vendors.
I’m running a 3x switchless Deepseek 4.1 Flash setup!
I’m familiar with the MikroTik unit. I did find stock in Europe.
The ebay listing for the Dell Powerswitch is roughly 3x this price but for 32 ports. It may make more sense if you’re looking to go that high density route.
I have a git repo with my DS41F build if you’d like to try it! :)
That DELL is a massive power hungry switch but is a steal for 32 400G port switch at ~$3.8K
I wouldn’t go beyond 2 connected MikroTik CRS804 switches where each switch carries 7 Sparks max and you leave 1 200G branch to connect the switches.
While 14 Sparks isn’t the 32 Spark-lab that fellow mentioned building, for me 14 (if I ever scale that high and if Spark supply re-emerges) would be my personal home-lab cap before any further expansion would need a formal dedicated temp controlled home-data-center.
For now I think I might have to patiently wait for Dec/Jan MikroTik CRS804 availability if there are no peers at their tier.
Yes, please share the repo I’m sure many would value your build! :)
Sharing a visual example Kevin had shared in May illustrating a single CRS804 config.
My numbers above (7+7) use one of the Y-cable branches to connect 2 CRS804 switches
For 4 nodes you can go single or dual CRS504, won’t let you go beyond that though.
CRS504 is the bare min for a capped 4×100G QSFP28 connection but has no room for scale unlike the CRS804’s 4× 400GQSFP-DD at the same price it would lack forward hedging.
There’s no need to connect the two switches since the Sparks have two ports. You can just connect each Spark to each switch. Then you can have an 8x cluster (which at least one user says is better performance using two CRS804) or a 16x cluster at 200Gbps. There’s no equivalent to the CRS804 as far as I know. A Z9332F-ON seems like the next cheapest option, but yes, it’s not comparable to the CRS804 and is total overkill for the purposes, with the power usage, noise, and heat to go along with it.
Edit: In your case I’d just get the CRS504 and then get a CRS804 when they’re available if you want it.
True since the CRS804 can break out 400G x 4 100G a cross switch topology would be cleaner and support a 16 Spark node Cluster
I was initially thinking of a maxed out 24 Node (12 + 12) Spark Cluster with a parallel 400G <—> 400G switch connection bridge but that can become a major cross switch bottleneck.
Edit: At the cost of $800 of the CRS504 and $1100 for the CRS804 I’m weighing the total impact of the daisy chain lag for 2-3 months vs. investing in the switch connected peace of mind.
Capturing cost-efficient switch scale options for Spark Node Clusters for 4+ Sparks:
Up to 3x Sparks
- Switch-less DAC
4-Spark Cluster Option
- MikroTik CRS504 4x 100G Ports (switch cost: ~$900)
4-8-Spark Option
- MikroTik CRS804 4x 400G Port with breakout DACs (switch cost: ~$1200)
8-16-Spark Option
- Dual-homed on MikroTik CRS804 4x 400G Port with breakout DACs (switch cost: ~$1200 x 2)
Alt up to 16 Spark Option
- MikroTik CRS520 16x 100G Port with direct DAC per Spark (switch unit cost range: ~$2100)
CRS804 my preferred choice is currently on back-order globally; CRS504’s temp, dBA and power draw make it a palatable quiet home-lab alternative albeit not as compact as the CRS804.
The switchless ring mesh is working really well. Not sure if we still need a switch for 4 sparks. Just make sure one of the cables is 0.5m instead of the 0.4m normally sold (to connect the outer sparks). I am currently waiting for the CRS804
That’s good to know. The 2nd bundle arrives early next week. I’ll test the ring once it arrives since I have 4 DACs.
It’s hidden away in a little known forum thread here:
There is the 4 node switchless option:
It does mean that there is always a node that will have to be ‘routed’ so some bandwidth will be lost for the direction communications.
Don’t stare yourself blind on just the switch prices. The 400G to 2x200G DACs will cost as much as the switch if you get 4. Now if you do the 100G QSFP28 DACs, they are peanuts in comparison.
You could get the CRS520 and plug in 2x100G DACs to each of your 8 nodes and still come out on top compared to the CRS804.
Edit - Typo