Issues to connect to email server when using a wired internet connection [Solved]

[Masi]

Hi all,

I send and receive emails with Thunderbird using email provider mailbox.org. I use IMAP with SSL/TLS as described on the provider's website https://kb.mailbox.org/en/private/faq-a ... s-manually

When Thunderbird connects to send/receive emails I noticed a material difference in terms of speed when I use a wired connection vs. wifi. With the wired connection it takes c. 30-60 seconds to connect. With wifi it takes max. 5 seconds to connect. I assume something is different in the way the connection is processed. Any ideas where to start looking?

Couple of things that might be important:
- Wired and wifi are using the same router. I observed no differences between both connection types when using the browser to open websites.
- Wired connection is via USB C coming from my monitor which is connected by cable to the router.

Thank you.

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System:
  Kernel: 6.1.0-16-amd64 [6.1.67-1] arch: x86_64 bits: 64 compiler: gcc v: 12.2.0
    parameters: BOOT_IMAGE=/vmlinuz-6.1.0-16-amd64 root=UUID=<filter> ro quiet splash
  Desktop: Xfce v: 4.18.1 tk: Gtk v: 3.24.36 info: xfce4-panel wm: xfwm v: 4.18.0 vt: 7
    dm: LightDM v: 1.26.0 Distro: MX-23.1_x64 Libretto July 31  2023 base: Debian GNU/Linux 12
    (bookworm)
Machine:
  Type: Laptop System: Dell product: Inspiron 7370 v: N/A serial: <superuser required> Chassis:
    type: 10 serial: <superuser required>
  Mobo: Dell model: 06KDFD v: A00 serial: <superuser required> UEFI: Dell v: 1.22.0
    date: 12/14/2021
Battery:
  ID-1: BAT0 charge: 13.5 Wh (98.5%) condition: 13.7/38.0 Wh (36.0%) volts: 13.2 min: 11.4
    model: BYD DELL RPJC386 type: Li-poly serial: <filter> status: charging
CPU:
  Info: model: Intel Core i5-8250U bits: 64 type: MT MCP arch: Coffee Lake gen: core 8 level: v3
    note: check built: 2017 process: Intel 14nm family: 6 model-id: 0x8E (142) stepping: 0xA (10)
    microcode: 0xF4
  Topology: cpus: 1x cores: 4 tpc: 2 threads: 8 smt: enabled cache: L1: 256 KiB
    desc: d-4x32 KiB; i-4x32 KiB L2: 1024 KiB desc: 4x256 KiB L3: 6 MiB desc: 1x6 MiB
  Speed (MHz): avg: 800 min/max: 400/1600 scaling: driver: intel_pstate governor: powersave
    cores: 1: 800 2: 800 3: 800 4: 800 5: 800 6: 800 7: 800 8: 800 bogomips: 28800
  Flags: avx avx2 ht lm nx pae sse sse2 sse3 sse4_1 sse4_2 ssse3 vmx
  Vulnerabilities:
  Type: gather_data_sampling mitigation: Microcode
  Type: itlb_multihit status: KVM: VMX disabled
  Type: l1tf mitigation: PTE Inversion; VMX: conditional cache flushes, SMT vulnerable
  Type: mds mitigation: Clear CPU buffers; SMT vulnerable
  Type: meltdown mitigation: PTI
  Type: mmio_stale_data mitigation: Clear CPU buffers; SMT vulnerable
  Type: retbleed mitigation: IBRS
  Type: spec_rstack_overflow status: Not affected
  Type: spec_store_bypass mitigation: Speculative Store Bypass disabled via prctl
  Type: spectre_v1 mitigation: usercopy/swapgs barriers and __user pointer sanitization
  Type: spectre_v2 mitigation: IBRS, IBPB: conditional, STIBP: conditional, RSB filling,
    PBRSB-eIBRS: Not affected
  Type: srbds mitigation: Microcode
  Type: tsx_async_abort status: Not affected
Graphics:
  Device-1: Intel UHD Graphics 620 vendor: Dell driver: i915 v: kernel arch: Gen-9.5
    process: Intel 14nm built: 2016-20 ports: active: DP-2 off: eDP-1 empty: DP-1,HDMI-A-1
    bus-ID: 00:02.0 chip-ID: 8086:5917 class-ID: 0300
  Device-2: Logitech C920 PRO HD Webcam type: USB driver: snd-usb-audio,uvcvideo
    bus-ID: 1-4.2.2:21 chip-ID: 046d:08e5 class-ID: 0102
  Device-3: Microdia Integrated_Webcam_HD type: USB driver: uvcvideo bus-ID: 1-5:2
    chip-ID: 0c45:6715 class-ID: 0e02
  Display: x11 server: X.Org v: 1.21.1.7 compositor: xfwm v: 4.18.0 driver: X:
    loaded: modesetting unloaded: fbdev,vesa dri: iris gpu: i915 display-ID: :0.0 screens: 1
  Screen-1: 0 s-res: 3440x1440 s-dpi: 96 s-size: 910x381mm (35.83x15.00") s-diag: 987mm (38.84")
  Monitor-1: DP-2 pos: primary model: ViewSonic VG3456 serial: <filter> built: 2022
    res: 3440x1440 hz: 60 dpi: 109 gamma: 1.2 size: 800x335mm (31.5x13.19") diag: 867mm (34.1")
    modes: max: 3440x1440 min: 720x400
  Monitor-2: eDP-1 note: disabled model: Sharp 0x1485 built: 2017 res: 3440x1440 dpi: 166
    gamma: 1.2 size: 294x165mm (11.57x6.5") diag: 337mm (13.3") ratio: 16:9 modes: 1920x1080
  API: OpenGL v: 4.6 Mesa 22.3.6 renderer: Mesa Intel UHD Graphics 620 (KBL GT2)
    direct-render: Yes
Audio:
  Device-1: Intel Sunrise Point-LP HD Audio vendor: Dell driver: snd_hda_intel v: kernel
    bus-ID: 1-4.1:17 alternate: snd_soc_skl,snd_sof_pci_intel_skl chip-ID: 0b0e:0305 class-ID: 0300
    bus-ID: 00:1f.3 chip-ID: 8086:9d71 serial: <filter> class-ID: 0403
  Device-2: GN Netcom Jabra EVOLVE Link MS type: USB driver: jabra,snd-usb-audio,usbhid
  Device-3: Logitech C920 PRO HD Webcam type: USB driver: snd-usb-audio,uvcvideo
    bus-ID: 1-4.2.2:21 chip-ID: 046d:08e5 class-ID: 0102
  API: ALSA v: k6.1.0-16-amd64 status: kernel-api tools: alsamixer,amixer
  Server-1: PipeWire v: 1.0.0 status: off with: 1: pipewire-pulse status: active 2: wireplumber
    status: off 3: pipewire-alsa type: plugin 4: pw-jack type: plugin
    tools: pactl,pw-cat,pw-cli,wpctl
Network:
  Device-1: Intel Wireless 7265 driver: iwlwifi v: kernel pcie: gen: 1 speed: 2.5 GT/s lanes: 1
    bus-ID: 01:00.0 chip-ID: 8086:095a class-ID: 0280
  IF: wlan0 state: up mac: <filter>
  Device-2: Realtek RTL8153 Gigabit Ethernet Adapter type: USB driver: r8152 bus-ID: 2-4.3:5
    chip-ID: 0bda:8153 class-ID: 0000 serial: <filter>
  IF: eth0 state: up speed: 1000 Mbps duplex: full mac: <filter>
Bluetooth:
  Device-1: Intel Bluetooth wireless interface type: USB driver: btusb v: 0.8 bus-ID: 1-7:3
    chip-ID: 8087:0a2a class-ID: e001
  Report: hciconfig ID: hci0 rfk-id: 1 state: up address: <filter> bt-v: 2.1 lmp-v: 4.2
    sub-v: 1000 hci-v: 4.2 rev: 1000
  Info: acl-mtu: 1021:5 sco-mtu: 96:6 link-policy: rswitch hold sniff
    link-mode: peripheral accept service-classes: object transfer
Drives:
  Local Storage: total: 238.47 GiB used: 174.19 GiB (73.0%)
  SMART Message: Unable to run smartctl. Root privileges required.
  ID-1: /dev/sda maj-min: 8:0 vendor: Toshiba model: KSG60ZMV256G M.2 2280 256GB size: 238.47 GiB
    block-size: physical: 4096 B logical: 512 B speed: 6.0 Gb/s type: SSD serial: <filter> rev: 4102
    scheme: GPT
Partition:
  ID-1: / raw-size: 34.98 GiB size: 34.14 GiB (97.58%) used: 11.78 GiB (34.5%) fs: ext4
    dev: /dev/dm-0 maj-min: 253:0 mapped: root.fsm
  ID-2: /boot raw-size: 512 MiB size: 487.2 MiB (95.16%) used: 191.5 MiB (39.3%) fs: ext4
    dev: /dev/sda2 maj-min: 8:2
  ID-3: /boot/efi raw-size: 256 MiB size: 252 MiB (98.46%) used: 6.5 MiB (2.6%) fs: vfat
    dev: /dev/sda1 maj-min: 8:1
Swap:
  Kernel: swappiness: 15 (default 60) cache-pressure: 100 (default)
  ID-1: swap-1 type: partition size: 7.99 GiB used: 0 KiB (0.0%) priority: -2 dev: /dev/dm-1
    maj-min: 253:1 mapped: luks-<filter>
Sensors:
  System Temperatures: cpu: 45.0 C pch: 43.5 C mobo: 43.0 C sodimm: SODIMM C
  Fan Speeds (RPM): cpu: 0
Repos:
  Packages: pm: dpkg pkgs: 2246 libs: 1169 tools: apt,apt-get,aptitude,nala,synaptic pm: rpm
    pkgs: 0 pm: flatpak pkgs: 0
  No active apt repos in: /etc/apt/sources.list
  Active apt repos in: /etc/apt/sources.list.d/debian-stable-updates.list
    1: deb http://deb.debian.org/debian bookworm-updates main contrib non-free non-free-firmware
  Active apt repos in: /etc/apt/sources.list.d/debian.list
    1: deb http://deb.debian.org/debian bookworm main contrib non-free non-free-firmware
    2: deb http://security.debian.org/debian-security bookworm-security main contrib non-free non-free-firmware
  Active apt repos in: /etc/apt/sources.list.d/librewolf.list
    1: deb [arch=amd64] http://deb.librewolf.net bookworm main
  Active apt repos in: /etc/apt/sources.list.d/mx.list
    1: deb https://mirror.23m.com/mx-packages/mx/repo/ bookworm main non-free
  Active apt repos in: /etc/apt/sources.list.d/signal-xenial-added-by-mxpi.list
    1: deb [arch=amd64] https://updates.signal.org/desktop/apt xenial main
  Active apt repos in: /etc/apt/sources.list.d/spotify.list
    1: deb http://repository.spotify.com stable non-free
Info:
  Processes: 276 Uptime: 2h 0m wakeups: 35505 Memory: 7.5 GiB used: 4.28 GiB (57.1%) Init: SysVinit
  v: 3.06 runlevel: 5 default: graphical tool: systemctl Compilers: gcc: 12.2.0 alt: 12
  Client: shell wrapper v: 5.2.15-release inxi: 3.3.26
Boot Mode: UEFI

[CharlesV]

Have you tested speeds across the wired connection?

Also, ip addresses, DNS servers and lag times across both.

Typically, a 30 second lag at the start of a process is either a connection lag or a dns lag. Connected 'via usb to monitor' is a rather strange connection and I suspect the issue is right there.

Can you test this wired straight to the router / switch?

[Masi]

Yes, I ran a speed check on fast.com. Wired and wifi are almost the same - both around 90 Mbps.

Unfortunately, my notebook does not have a network port. For this reason I use the monitor for the wired connection. I also use the wired connection on a windows machine. No issues there with email.

What checks can I do to identify lag time differences between both approaches?

[CharlesV]

So, first, see what your IP addresses are for both wifi and USB -

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ip address  

then also the route on both

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route 

DSN is also a question - a dsn lookup that is timing out is roughly 30 to 60 seconds.. so looking up that server could be a problem.
For this, connect using the wifi and then do

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cat /etc/resolv.conf 

then disconnect wifi and connect to the USB and do this again

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cat /etc/resolv.conf 

I am going to also suggest that you disconnect from wifi, restart your machine so it comes up on the USB network FIRST and then check this lag.

[Masi]

Checked if I experience the same issue when I run MX Linux in a virtual machine. No issues with Thunderbird in the VirtualBox when I am connected to wired only on the host system. See QSI below for the virtual machine.

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System:
  Kernel: 6.1.0-16-amd64 [6.1.67-1] arch: x86_64 bits: 64 compiler: gcc v: 12.2.0
    parameters: BOOT_IMAGE=/vmlinuz-6.1.0-16-amd64 root=UUID=<filter> ro quiet splash
  Desktop: Xfce v: 4.18.1 tk: Gtk v: 3.24.36 info: xfce4-panel wm: xfwm v: 4.18.0 vt: 7
    dm: LightDM v: 1.26.0 Distro: MX-23.1_x64 Libretto July 31  2023 base: Debian GNU/Linux 12
    (bookworm)
Machine:
  Type: Virtualbox System: innotek GmbH product: VirtualBox v: 1.2 serial: <superuser required>
    Chassis: Oracle Corporation type: 1 serial: <superuser required>
  Mobo: Oracle model: VirtualBox v: 1.2 serial: <superuser required> BIOS: innotek GmbH
    v: VirtualBox date: 12/01/2006
Battery:
  ID-1: BAT0 charge: 50.0 Wh (100.0%) condition: 50.0/50.0 Wh (100.0%) volts: 10.0 min: 10.0
    model: innotek 1 type: Unknown serial: N/A status: full
CPU:
  Info: model: Intel Core i5-8250U bits: 64 type: MCP arch: Coffee Lake gen: core 8 level: v2
    built: 2017 process: Intel 14nm family: 6 model-id: 0x8E (142) stepping: 0xA (10) microcode: N/A
  Topology: cpus: 1x cores: 4 smt: <unsupported> cache: L1: 256 KiB desc: d-4x32 KiB; i-4x32 KiB
    L2: 1024 KiB desc: 4x256 KiB L3: 24 MiB desc: 4x6 MiB
  Speed (MHz): avg: 1799 min/max: N/A cores: 1: 1799 2: 1799 3: 1799 4: 1799 bogomips: 14393
  Flags: avx avx2 ht lm nx pae sse sse2 sse3 sse4_1 sse4_2 ssse3
  Vulnerabilities:
  Type: gather_data_sampling status: Unknown: Dependent on hypervisor status
  Type: itlb_multihit status: KVM: VMX unsupported
  Type: l1tf mitigation: PTE Inversion
  Type: mds mitigation: Clear CPU buffers; SMT Host state unknown
  Type: meltdown mitigation: PTI
  Type: mmio_stale_data mitigation: Clear CPU buffers; SMT Host state unknown
  Type: retbleed status: Vulnerable
  Type: spec_rstack_overflow status: Not affected
  Type: spec_store_bypass status: Vulnerable
  Type: spectre_v1 mitigation: usercopy/swapgs barriers and __user pointer sanitization
  Type: spectre_v2 mitigation: Retpolines, STIBP: disabled, RSB filling, PBRSB-eIBRS: Not
    affected
  Type: srbds status: Unknown: Dependent on hypervisor status
  Type: tsx_async_abort status: Not affected
Graphics:
  Device-1: VMware SVGA II Adapter driver: vmwgfx v: 2.20.0.0 ports: active: Virtual-1
    empty: Virtual-2, Virtual-3, Virtual-4, Virtual-5, Virtual-6, Virtual-7, Virtual-8
    bus-ID: 00:02.0 chip-ID: 15ad:0405 class-ID: 0300
  Display: x11 server: X.Org v: 1.21.1.7 compositor: xfwm v: 4.18.0 driver: X: loaded: vmware
    unloaded: fbdev,modesetting,vesa dri: swrast gpu: vmwgfx display-ID: :0.0 screens: 1
  Screen-1: 0 s-res: 2043x1125 s-dpi: 96 s-size: 541x298mm (21.30x11.73") s-diag: 618mm (24.32")
  Monitor-1: Virtual-1 mapped: Virtual1 res: 2043x1125 hz: 60 size: N/A modes: max: 2043x1125
    min: 640x480
  API: OpenGL v: 4.5 Mesa 22.3.6 renderer: llvmpipe (LLVM 15.0.6 256 bits) direct-render: Yes
Audio:
  Device-1: Intel 82801AA AC97 Audio vendor: Dell driver: snd_intel8x0 v: kernel bus-ID: 00:05.0
    chip-ID: 8086:2415 class-ID: 0401
  API: ALSA v: k6.1.0-16-amd64 status: kernel-api tools: alsamixer,amixer
  Server-1: PipeWire v: 1.0.0 status: active with: 1: pipewire-pulse status: active
    2: wireplumber status: active 3: pipewire-alsa type: plugin 4: pw-jack type: plugin
    tools: pactl,pw-cat,pw-cli,wpctl
Network:
  Device-1: Intel 82540EM Gigabit Ethernet driver: e1000 v: kernel port: d020 bus-ID: 00:03.0
    chip-ID: 8086:100e class-ID: 0200
  IF: eth0 state: up speed: 1000 Mbps duplex: full mac: <filter>
  Device-2: Intel 82371AB/EB/MB PIIX4 ACPI type: network bridge driver: piix4_smbus v: N/A
    modules: i2c_piix4 port: N/A bus-ID: 00:07.0 chip-ID: 8086:7113 class-ID: 0680
Drives:
  Local Storage: total: 30 GiB used: 7.5 GiB (25.0%)
  SMART Message: Unable to run smartctl. Root privileges required.
  ID-1: /dev/sda maj-min: 8:0 vendor: VirtualBox model: VBOX HARDDISK size: 30 GiB block-size:
    physical: 512 B logical: 512 B speed: 3.0 Gb/s type: N/A serial: <filter> rev: 1.0 scheme: MBR
Partition:
  ID-1: / raw-size: 9.84 GiB size: 9.59 GiB (97.44%) used: 7.31 GiB (76.3%) fs: ext4 dev: /dev/dm-0
    maj-min: 253:0 mapped: luks-<filter>
  ID-2: /boot raw-size: 1024 MiB size: 973.4 MiB (95.06%) used: 191 MiB (19.6%) fs: ext4
    dev: /dev/sda1 maj-min: 8:1
Swap:
  Kernel: swappiness: 15 (default 60) cache-pressure: 100 (default)
  ID-1: swap-1 type: partition size: 7.8 GiB used: 0 KiB (0.0%) priority: -2 dev: /dev/dm-1
    maj-min: 253:1 mapped: luks-<filter>
Sensors:
  Src: lm-sensors+/sys Message: No sensor data found using /sys/class/hwmon or lm-sensors.
Repos:
  Packages: pm: dpkg pkgs: 2081 libs: 1059 tools: apt,apt-get,aptitude,nala,synaptic pm: rpm
    pkgs: 0 pm: flatpak pkgs: 0
  No active apt repos in: /etc/apt/sources.list
  Active apt repos in: /etc/apt/sources.list.d/debian-stable-updates.list
    1: deb http://deb.debian.org/debian bookworm-updates main contrib non-free non-free-firmware
  Active apt repos in: /etc/apt/sources.list.d/debian.list
    1: deb http://deb.debian.org/debian bookworm main contrib non-free non-free-firmware
    2: deb http://security.debian.org/debian-security bookworm-security main contrib non-free non-free-firmware
  Active apt repos in: /etc/apt/sources.list.d/mx.list
    1: deb http://ftp.halifax.rwth-aachen.de/mxlinux/packages/mx/repo/ bookworm main non-free
Info:
  Processes: 215 Uptime: 5m wakeups: 41 Memory: 3.82 GiB used: 1.02 GiB (26.6%) Init: SysVinit
  v: 3.06 runlevel: 5 default: graphical tool: systemctl Compilers: gcc: 12.2.0 alt: 12
  Client: shell wrapper v: 5.2.15-release inxi: 3.3.26
Boot Mode: BIOS (legacy, CSM, MBR)

Also ran the other commands and did a restart before with wifi deactived. Please see below.

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$ ip address
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host 
       valid_lft forever preferred_lft forever
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
    link/ether 00:d2:b1:d4:90:1b brd ff:ff:ff:ff:ff:ff
    inet 192.168.0.177/24 brd 192.168.0.255 scope global dynamic noprefixroute eth0
       valid_lft 604613sec preferred_lft 604613sec
    inet6 2a02:908:175:5280:1f4c:c8fd:ec11:3ad2/128 scope global dynamic noprefixroute 
       valid_lft 604615sec preferred_lft 604615sec
    inet6 2a02:908:175:5280:9143:4eb9:735e:2603/64 scope global dynamic noprefixroute 
       valid_lft 86401sec preferred_lft 43201sec
    inet6 fe80::b340:ec5c:b203:c5e/64 scope link noprefixroute 
       valid_lft forever preferred_lft forever
3: wlan0: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN group default qlen 1000
    link/ether e2:ad:b4:3e:2b:e4 brd ff:ff:ff:ff:ff:ff permaddr 14:4f:8a:34:cb:f5

wired:

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$ route
Kernel-IP-Routentabelle
Ziel            Router          Genmask         Flags Metric Ref    Use Iface
default         _gateway        0.0.0.0         UG    100    0        0 eth0
192.168.0.0     0.0.0.0         255.255.255.0   U     100    0        0 eth0

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cat /etc/resolv.conf 
# Generated by NetworkManager
nameserver 192.168.0.100
nameserver 192.168.0.1
nameserver 2a02:908:175:5280:10:18ff:fe97:6244

wifi:

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$ route
Kernel-IP-Routentabelle
Ziel            Router          Genmask         Flags Metric Ref    Use Iface
default         _gateway        0.0.0.0         UG    600    0        0 wlan0
192.168.0.0     0.0.0.0         255.255.255.0   U     600    0        0 wlan0

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# Generated by NetworkManager
nameserver 192.168.0.100
nameserver 192.168.0.1
nameserver 2a02:908:175:5280:10:18ff:fe97:6244

[CharlesV]

Interesting... so your machine is getting tied up, but yet route to your gateway( the same one) switches properly and DNS is the same...

Hmm.. what is your USb connection connecting too? You said monitor, but which and what ?

[Masi]

I am have this one https://www.viewsonic.com/us/vg3456a.html

The monitor is connected to the router via ethernet cable and supplies internet over usb c to the notebook.

Also tied another email software. Same behavior.

[CharlesV]

I am have this one https://www.viewsonic.com/us/vg3456a.html

The monitor is connected to the router via ethernet cable and supplies internet over usb c to the notebook.

Also tied another email software. Same behavior.

I have to suspect that your computer is getting hung up on trying the wifi route first, timing out and then hitting the wired connection. (This would make sense of why the VM works fine.)

The other possibility... is the shared USB-C port (But the VM working properly kind of negates that.) If your laptop has another usb port, I am going to suggest trying a usb network adapter and see if this resolves it. Having multiple devices on your current USB-C my be the issue here.

You might also try
1) Try Disabling both wired and wireless, wait a minute or so, and then enable only the wired and test it.
2) Disable IPV6 ( Possibly the monitor isnt handling it well?)
3) Setting a static route on the wired - static IP, Static DNS, add a route manually, leave wireless dhcp and turned off. (not just disconnected. )

[Masi]

Thanks - disabling IPv6 for the wired connection solved the problem.

But still wondering for the underlying issue for the delay as the VM worked fine (with IPv6 on the host still activated). Question is, is it the monitor that causes the issue or any specific configuration on my linux machine.

[CharlesV]

Glad you have it resolved. Please mark as solved using the check mark on the top right of the post that resolved it.

There are a couple of possibilities here.
First - by nature IPv6 is more mindful of how things work. ( routers, relays etc) , so it is very possible that things are being twisted up in the route.

Second - Many devices *still* are not IPv6 compliant. (My suspicion is it's this and the monitor )

Third - Since your computer HAS worked with IPv6, networking should attempt to use that first. So when you switch over to wired it tries too. But, ipv6 timesout, so it falls back to IPv4. The VM has never completed an IPv6 packet, so there is no route to n IPv6 device only to the 4.