- Thursday, October 23, 2025
MikroTik’s Cloud Hosted Router (CHR) – the virtualized version of RouterOS – has just gotten a significant upgrade. Users running CHR on hypervisors (like Proxmox or other KVM platforms) have long faced a frustrating bandwidth bottleneck. Even on 10Gbps virtual NICs, CHR instances often topped out around 3–5 Gbps of throughput. This was especially evident in setups using Virtio network drivers, where enabling features like FastTrack could drop throughput as low as ~3 Gbps. The good news is that the latest RouterOS v7.20 release has resolved this performance issue, delivering dramatically higher speeds for CHR in virtual environments.
The Virtio Bottleneck: CHR Performance Issues on Proxmox (KVM)
Virtualization platforms typically use Virtio paravirtualized drivers for network interfaces. CHR is optimized for virtual machines, but until now, its Virtio network performance lagged far behind expectations. Community members shared cases where a CHR on Proxmox (with a 10G virtual NIC) could only achieve ~5 Gbps throughput in iperf3 tests. By comparison, standard Linux VMs or other virtual routers could push much more traffic over the same virtual infrastructure, pointing to a CHR-specific limitation. CPU usage wasn’t even maxed out – indicating an inefficiency in how CHR handled the Virtio network interface.
This issue wasn’t limited to one user. Others reported similar constraints: for instance, a CHR routing between VMs on a 25G host network was stuck around 2.5–3 Gbps, whereas a Linux VM could do 10–20+ Gbps in the same scenario. Many suspected the Virtio driver implementation in RouterOS was the culprit. Some advanced users attempted workarounds like SR-IOV (direct NIC virtualization) to bypass Virtio, but that adds complexity. What CHR really needed was a fix within RouterOS – and MikroTik has delivered precisely that with the new update.
RouterOS 7.20: Improved Virtio Drivers and 10× Throughput Gains
RouterOS v7.20 (stable) was released at the end of September 2025, and it explicitly includes a fix for this long-standing issue. In the official v7.20 release notes, MikroTik lists “chr - improved virtio_net performance” as one of the new changes. In other words, the virtual NIC (Virtio) driver in CHR has been optimized in 7.20 to unlock much higher bandwidth. Early adopters of v7.20 report that the difference is night and day.
According to user benchmarks, upgrading to RouterOS 7.20 instantly removes the bottleneck. One Proxmox-based lab setup saw CHR’s routing throughput jump from about 2.5–3 Gbps to 22–24 Gbps just by moving from RouterOS v7.18.2 to v7.20. That’s nearly a tenfold increase, bringing performance in line with what the underlying 25G network can deliver (roughly 85–90% of line rate in this case). Even with firewall and NAT rules in place, CHR is now approaching wire-speed forwarding on 10G+ virtual interfaces. “I’m super happy with that,” one user reported after seeing these results, urging anyone with the same problem to upgrade to ≥7.20 and enjoy the improvement.
Significantly, this fix benefits any virtual environment using Virtio drivers – not just Proxmox. Whether you run CHR on Proxmox, VMware (with appropriate drivers), Hyper-V, or other cloud platforms, RouterOS 7.20’s enhanced Virtio networking should unlock significantly higher throughput. MikroTik essentially reworked how RouterOS interacts with the Virtio-Net interface, eliminating the previous inefficiencies. The result is that CHR can finally utilize high-speed virtual NICs to their full potential, closing the gap between virtual routers and their physical hardware counterparts.
How to Upgrade Your CHR to RouterOS 7.20
Upgrading to the new version is straightforward, and it’s the key to unleashing these performance gains. Before starting, always back up your CHR’s configuration (and license key) and ensure the router won’t lose power during the upgrade. Once that’s done, you have two primary upgrade methods:
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Use the built-in update tool: Log in to your CHR’s management interface (WinBox or WebFig). Navigate to System → Packages and click “Check For Updates.” Make sure you’re on the “stable” release channel. RouterOS should detect the v7.20 update; proceed to download and install it. The CHR will automatically reboot into RouterOS 7.20. (MikroTik’s official guidance: “click ‘Check for updates’ at /system package in your RouterOS interface”).
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Manual upgrade via disk image: Alternatively, you can download the latest CHR 7.20 disk image from the MikroTik website and install it manually. The CHR images (in VMDK, VHDX, VDI, OVA, etc.) for the stable 7.20 release are available on the MikroTik download page. You could attach the new image to a VM, use it to deploy a fresh CHR instance, and then import your backup. This method is helpful if you prefer a clean install or cannot use the automatic online update.
After upgrading, verify the RouterOS version (it should show 7.20 in /system resource print or WinBox) and then test your network throughput. You should immediately notice the difference – for example, previously capped links will now reach much higher speeds without additional tweaking. The improvement should be especially obvious on 10G, 25G, or 40G virtual interfaces where CHR 7.19 and below struggled to utilize the full bandwidth.
Conclusion
For MikroTik users running CHR in a virtualized environment, RouterOS 7.20 is a must-have upgrade. It resolves the critical performance limitations of earlier versions, allowing your virtual router to perform on par with expectations. Where you might have been limited to a few Gbps before, you can now potentially push tens of Gbps through a CHR VM. This not only validates CHR as a viable high-performance router for cloud and virtualization, but it also means simpler setups – you may no longer need exotic workarounds like SR-IOV or physical hardware to reach your throughput goals.
If you’ve experienced bandwidth issues or are planning to deploy CHR for heavy network loads, consider upgrading to RouterOS 7.20 and giving it a try. The combination of MikroTik’s feature-rich RouterOS with these new performance improvements makes CHR more potent than ever for virtual networking scenarios. With just a few clicks to update, you’ll unlock the full potential of your virtual router and be ready to route at blazing speeds. Happy upgrading, and enjoy the fast lanes now open to MikroTik CHR!