Graylog 5 not possible in HyperV RHEL8

We run GL on HyperV / RHEL8
GL5 requires Mongo5+
Mongo5+ requires AVX cpu extensions
HyperV does not provide AVX (VMWare apparently can)
Result = you can’t run GL5+ on HyperV it seems.
Nor can you run later version of mongodb for other needs

Unless someone has an answer to this. I found no back door way in the googleverse to enable AVX in HyperV.


This is true, if the CPU does not have the flag AVX then MongoDb will not run, hence Graylog 5 will not work. This is unfortunate.
I close my post out since there not much I can do.

If I’m reading the linked GitHub right it sounds like if your CPUs in your server support AVX, you need to just confirm you have processor compatibility mode disabled on the Guest for Graylog and AVX should then be passed by Hyper-v the guest OS.

We run HA Clustering in our HyperV infrastructure for which I’m told we are required to enable compat. mode. But thanks for the catch. I can test that even if I can’t use it.

That should only be required if the nodes in your cluster don’t have the similar generation CPUs. Goodluck with you testing please report back as I’ll be looking to upgrade to GL 4.3.9 soon and also run it on Hyper-v.

We are not homogeneous.


Yeah that was the first thing we tried. Further down that post I posted my cat /proc/cpuinfo


Flag for AVX is not shown but I do have SSE which mongo also suggest to have.

EDIT: basically for the socket we have I dont think right now our MB can support CPU with AVX

Hi Gsmith, so is it a limitation of your CPU hardware or the hypervisor?

Exactly, they are old CPU’s, so we use them for our Dev ops before going into production. Every Opensource software product we use, not one problem until now with MongoDb. If you work in a data center then you know a blade servers is not cheap, some are more then a house , times that by 576 servers.

EDIT: Yeah you really have to look up your CPU to make sure it has AVX flag, plus if the sock does not have a compalible CPU, then you will need motherboard and CPU.

I’ve got to assume that if enough paid Graylog customers suddenly can’t run Graylog because of this issue either Mongo will be replaced, or a work around will be found. After all, the only reason they made that requirement in mongodb was performance. And for Graylog purposes I doubt the performance matters at all.

Chances are custumer that have paid version probably will not get impacted, they could migrate to Graylog Cloud, or were prewarned about MongoDb. I should have paid attention to MongoDb forum about version 5 last year.

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Yeah, I was just wanting to confirm it was definitely a cpu hardware limitation and not a hyper-v limitation like OP suggested.

It IS a Hyper-V limitation. In the sense that if you have the CPU needed but you can’t disable cpu compatibility mode, HyperV will prevent mongo from working. This is my use case.

Hey, look up your CPU spec’s, if it doesn’t support AVX then you know what’s up.

Or if you need compatibility mode to support heterogeneous hardware in a HyperV cluster.

Running on proxmox with docker running on debian here…
Had similar issue with Mongo5…

Mongo 6 works perfectly fine so far.

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