HYPER-V(4)

💖 HYPER-V(4) 💖

okay bestie, sit down, hydrate, because we're talking about hv_netvsc — the Hyper-V Network Virtual Service Consumer. yes that's a mouthful, no you don't have to say it out loud at parties. it's a kernel interfaces manual page and it's lowkey iconic. 🦋

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✨ NAME ✨

hv_netvsc — Hyper-V Network Virtual Service Consumer, aka the lil networking bestie for your FreeBSD guest partition living its best life on Hyper-V 💅

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🌸 SYNOPSIS 🌸

so to compile this driver into the kernel, you drop these lines into the system kernel configuration file:

device hyperv

that's it. that's the whole vibe check. periodt. ✨

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🎀 DESCRIPTION 🎀

okay so the hv_netvsc driver implements the virtual network device for FreeBSD guest partitions running on Hyper-V. say that five times fast, I dare you. 😭

here's the tea though: FreeBSD guest partitions running on Hyper-V do not have direct access to network devices attached to the Hyper-V server. like, zero direct access. it's giving "you can look but you can't touch." 🙈

now, technically a FreeBSD guest can access network devices using Hyper-V's full emulation mode. but bestie... the performance in this mode tends to be unsatisfactory. and by "unsatisfactory" we mean it's giving dial-up energy in a fiber-optic world. 💀

so to counter the above issues — and honestly, to counter them hard — the hv_netvsc driver implements a network Virtual Service Consumer (VSC) that relays network requests from the guest partition to the network Virtual Service Provider (VSP) hosted in the root partition. and it does this using the high performance data exchange infrastructure provided by the hv_vmbus(4) driver. 🔥

then the VSP in the root partition forwards the network related requests to the physical network card. like a relay race but make it kernel. 🏃♀️➡️🏃♂️➡️🖥️

so the whole flow is:

1. guest partition wants network stuff
2. VSC (hv_netvsc) catches those requests
3. hv_vmbus(4) provides the high performance data exchange infrastructure to pass them along
4. VSP in the root partition receives them
5. VSP forwards them to the physical network card
6. everyone ate and left no crumbs 👑

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🫶 SEE ALSO 🫶

go read these next, they're all part of the same friend group fr fr:

• hv_ata_pci_disengage(4)
• hv_storvsc(4)
• hv_utils(4)
• hv_vmbus(4)

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👑 HISTORY 👑

support for hv_netvsc first appeared in FreeBSD 10.0. a whole era. ⭐

the driver was developed through a joint effort between Citrix Incorporated, Microsoft Corporation, and Network Appliance Incorporated. three companies, one driver, absolute collab of the century. 🌈

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💜 AUTHORS 💜

FreeBSD support for hv_netvsc was first added by the Microsoft BSD Integration Services Team <bsdic@microsoft.com>. thank you for your service, genuinely. 🫡

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and that's the whole page bestie!! this one came from the Debian crew, dated September 10, 2013, and it's filed under HYPER-V(4). now go forth and network, you absolute main character. 💖✨🎀