Guest VM Network Download Bandwidth Issue

[john_morris]

I'm not sure if this is a host problem or guest problem. I have not found a solution that works for me from my searches. Using VirtualBox 6.1.30-148432

Linux Host (Ubuntu 18.04 Server). Linux Guests (Ubuntu 20.04 Server) All guests have the same problem. The expected bandwidth is 100Mb/40Mb

The Guest VM gets roughly 5-10% of the download bandwidth of the host.

Below is a tiny sample of tests. For this sample, I ran two tests on the host, when completed, it was followed immediately by two tests on the guest. The guest is a fresh base install of ubuntu server, with only openssh-server, python3-pip, speedtest-cli, and vbox guest additions installed on it.

------- Host Bandwidth -------
admin@vm-host:~$ speedtest-cli
Retrieving speedtest-dot-net configuration...
Testing from ISP (88.88.188.210)...
Retrieving speedtest-dot-net server list...
Selecting best server based on ping...
Hosted by DP, Inc (Anytown, CA) [104.86 km]: 39.45 ms
Testing download speed................................................................................
Download: 81.14 Mbit/s
Testing upload speed......................................................................................................
Upload: 35.42 Mbit/s
admin@vm-host:~$ speedtest-cli
Retrieving speedtest-dot-net configuration...
Testing from ISP (88.88.188.210)...
Retrieving speedtest-dot-net server list...
Selecting best server based on ping...
Hosted by DP, Inc (Anytown, CA) [104.86 km]: 40.921 ms
Testing download speed................................................................................
Download: 97.73 Mbit/s
Testing upload speed......................................................................................................
Upload: 37.29 Mbit/s

------- Guest Bandwidth -------
admin@guest-vm:~$ speedtest-cli
Retrieving speedtest-dot-net configuration...
Testing from ISP (88.88.188.210)...
Retrieving speedtest-dot-net server list...
Selecting best server based on ping...
Hosted by DP, Inc (Anytown, CA) [104.86 km]: 38.597 ms
Testing download speed................................................................................
Download: 8.05 Mbit/s
Testing upload speed......................................................................................................
Upload: 37.76 Mbit/s
admin@guest-vm:~$ speedtest-cli
Retrieving speedtest-dot-net configuration...
Testing from ISP (88.88.188.210)...
Retrieving speedtest-dot-net server list...
Selecting best server based on ping...
Hosted by DTS Inc. (Anytown, NV) [73.17 km]: 36.414 ms
Testing download speed................................................................................
Download: 5.91 Mbit/s
Testing upload speed......................................................................................................
Upload: 39.25 Mbit/s

Upload bandwidth works great. Any ideas on download bandwidth?

[scottgus1]

There is a possibility a network bandwidth clamp has been placed, see https://www.virtualbox.org/manual/ch06. ... idth_limit

Please let's look at the VM's recipe:
Please right-click the VM in the main Virtualbox window's VM list, choose "Show in Explorer/Finder/File Manager". In the window that opens, zip the VM's .vbox file (not the .vbox-prev file), and post the zip file, using the forum's Upload Attachment tab. (Please make sure all file extensions are shown, so you will be able to see the .vbox extension easier.)

[john_morris]

I created the VM using all CLI commands and didn't put any restrictions on bandwidth

Also, I've tried different "nictype"s as well


I've attached the vbox file

[scottgus1]

Thanks! I don't see bandwidth clamps in place either. But I also see the VM only using one processor, so maybe two would help. As best I understand it, the VM network speed should be about the same as the host network, unless the VM is too busy doing something else to take the data in.

[john_morris]

I added a cpu, no changes. even a single cpu doesn't go above 10% during those tests.

frustrating.

[fth0]

What happens if you use the NAT networking mode instead of the Bridged networking mode?

[john_morris]

I'm using bridge mode because the host has a couple of 'trunk' ethernet ports, and I need to bridge into those ports and tag vlans on the trunk in the client.