Slow network in F35 and F36

After a botched upgrade from F33 to F36, followed by a fresh install, both F35 and F36 KDE versions give really poor network performance. DNF was working fast originally but slowed eventually down to a crawl, see screen shot.

The performance is really noticeable with web browsing. Chromium seems to work fine with but nothing else, which is the only oddity. Makes me think of DNS something that has changed (DoH?)

This is a fresh install of F36 with only Chromium and Nvidia drivers installed. It lives as a VM on ESXi so the network driver is vmxnet3 (although the problem persists whatever virtual NIC I give it) No other VM has such issues, and F33 was working just fine a day ago.

I don’t have the skills to troubleshoot this myself so I hope I don’t have to go to SUSE or some other distribution.


Welcome to ask :fedora: @sunborn

We really need info about your hardware to be able to troubleshoot.
Please post info in text here by copy&paste within the </> Preformatted text tags. It is easier to read than images and we can also copy&paste from it when in text format.

Please show us the output of inxi -Fzxx.

Can you also give us a screenshot of the results from running the test at

Sounds like it might be a systemd-resolved issue. Are you able to resolve the domains with resolvectl?

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Thank you, this just resolves to default gateway:

$ resolvectl
       Protocols: LLMNR=resolve -mDNS -DNSOverTLS DNSSEC=no/unsupported
resolv.conf mode: stub

Link 2 (ens192)
    Current Scopes: DNS LLMNR/IPv4 LLMNR/IPv6
         Protocols: +DefaultRoute +LLMNR -mDNS -DNSOverTLS DNSSEC=no/unsupported
Current DNS Server:
       DNS Servers:

Speedtest is normal

I don’t think this is any more information than I already provided other than specific CPU/GPU models.

$ inxi -Fzxx
  Kernel: 5.18.19-200.fc36.x86_64 arch: x86_64 bits: 64 compiler: gcc
    v: 2.37-27.fc36 Desktop: KDE Plasma v: 5.25.4 tk: Qt v: 5.15.5
    wm: kwin_wayland dm: SDDM Distro: Fedora release 36 (Thirty Six)
  Type: Vmware System: VMware product: VMware Virtual Platform v: N/A
    serial: <superuser required> Chassis: No Enclosure type: 1
    serial: <superuser required>
  Mobo: Intel model: 440BX Desktop Reference Platform
    serial: <superuser required> BIOS: Phoenix v: 6.00 date: 12/12/2018
  Info: 4x 1-core model: Intel Xeon E5-2687W v3 bits: 64 type: SMP
    arch: Haswell rev: 2 cache: L1: 4x 64 KiB (256 KiB)
    L2: 4x 256 KiB (1024 KiB) L3: 4x 25 MiB (100 MiB)
  Speed (MHz): avg: 3100 min/max: N/A cores: 1: 3100 2: 3100 3: 3100
    4: 3100 bogomips: 24799
  Flags: avx avx2 lm nx pae sse sse2 sse3 sse4_1 sse4_2 ssse3
  Device-1: NVIDIA GP108 [GeForce GT 1030] vendor: Micro-Star MSI
    driver: nvidia v: 515.65.01 arch: Pascal pcie: speed: 5 GT/s lanes: 32
    ports: active: none off: DP-1 empty: HDMI-A-1 bus-ID: 1b:00.0
    chip-ID: 10de:1d01
  Display: wayland server: v: 1.20.14 with: Xwayland v: 22.1.3
    compositor: kwin_wayland driver: X: loaded: nvidia
    unloaded: fbdev,modesetting,nouveau,vesa alternate: nv gpu: nvidia
    display-ID: 0
  Monitor-1: DP-1 res: 1280x1024 size: N/A
  OpenGL: renderer: NVIDIA GeForce GT 1030/PCIe/SSE2
    v: 4.6.0 NVIDIA 515.65.01 direct render: Yes
  Device-1: NVIDIA GP108 High Definition Audio vendor: Micro-Star MSI
    driver: snd_hda_intel v: kernel pcie: speed: 5 GT/s lanes: 32
    bus-ID: 1b:00.1 chip-ID: 10de:0fb8
  Sound Server-1: ALSA v: k5.18.19-200.fc36.x86_64 running: yes
  Sound Server-2: PulseAudio v: 15.0 running: no
  Sound Server-3: PipeWire v: 0.3.56 running: yes
  Device-1: Intel 82371AB/EB/MB PIIX4 ACPI vendor: VMware Virtual Machine
    type: network bridge driver: N/A port: N/A bus-ID: 00:07.3
    chip-ID: 8086:7113
  Device-2: VMware VMXNET3 Ethernet driver: vmxnet3 v: pcie:
    speed: 5 GT/s lanes: 32 port: 5000 bus-ID: 0b:00.0 chip-ID: 15ad:07b0
  IF: ens192 state: up speed: 10000 Mbps duplex: full mac: <filter>
  Local Storage: total: 600 GiB used: 5.2 GiB (0.9%)
  ID-1: /dev/sda model: Virtual disk size: 100 GiB serial: N/A
  ID-2: /dev/sdb model: Virtual disk size: 500 GiB serial: N/A
  ID-1: / size: 100 GiB used: 5.2 GiB (5.2%) fs: btrfs dev: /dev/sda1
  ID-1: swap-1 type: zram size: 7.75 GiB used: 0 KiB (0.0%) priority: 100
    dev: /dev/zram0
  Message: No sensor data found. Is lm-sensors configured?
  Processes: 664 Uptime: 15h 17m Memory: 7.75 GiB used: 3.06 GiB (39.5%)
  Init: systemd v: 250 target: graphical (5) default: graphical Compilers:
  gcc: 12.2.1 Packages: N/A note: see --pkg Shell: Bash v: 5.1.16
  running-in: konsole inxi: 3.3.19

Try resolving the hosts that failed in your screenshot with it, please., etc. Does they resolve and do they do so quickly?

Problem seems to have went away. $resolvectl query found no issues.

Websites seem to resolve in time now. I would leave it down to a repository issue but it clearly wasn’t confined to repos, even earlier today. and this website were slow to resolve, now working fine.

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Could have been an issue with your ISP’s DNS.

It doesn’t make sense since no other device had this problem. I am going to close this since the problem just somehow went away.

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