Questions[windows-subsystem-for-linux](server)

I try to access it through my windows browser and fail. what is my mistake?

I use WSL2 on windows 10, with ubuntu 20.
I have an apache server and a laravel app which I installed at /var/www/law
In my windows hosts file I've added this:

127.0.0.1   law.dev
::1 law.dev

and this is the law.conf file which is located at /etc/apache2/sites-available.

<VirtualHost *:80>
    ServerName law.dev


    DocumentRoot /var/www/law/public

    <Directory /var/www/law>
    Options Indexes MultiViews
    AllowOverride None
    Require all granted
    </Directory>

    ErrorLog ${APACHE_LOG_DIR}/error.log
    CustomLog ${APACHE_LOG_DIR}/access.log combined
</VirtualHost>

While attempting to clone a remote Git repo using SSH I got the following error:

git clone user@remote-repo:project.git .
remote: Counting objects: 187444, done.
remote: Compressing objects: 100% (73430/73430), done.
client_loop: send disconnect: Broken pipe.06 MiB | 4.04 MiB/s
fetch-pack: unexpected disconnect while reading sideband packet
fatal: early EOF
fatal: index-pack failed

My environment has the following Specs:

• WSL2 (Windows Subsystem 4 Linux)
• git --version git version 2.30.1

The git package can be found here https://pkgs.alpinelinux.org/package/edge/main/x86_64/git

uname -a
Linux 4.19.128-microsoft-standard #1 SMP Tue Jun 23 12:58:10 UTC 2020 x86_64 Linux

2021-03-09-07:11AM wsl@Alpine:~$ more /etc/issue
Welcome to Alpine Linux 3.10
Kernel \r on an \m (\l)

I've got no clue why is this happening. Is it a bursting or kernel configuration issue on Alpine? WSL? I doubt it's the remote host. The remote host works fine for SSH, as well as cloning for every non-WSL user.

I'm trying to follow this tutorial to run KVM nested in WSL 2, but after following the directions through compiling the kernel and loading it, the test kvm-ok reports that KVM is not supported.

I've tried multiple options: enabling hyper-v, disabling it, verifying BIOS/CPU support, enabling/disabling Device Guard, other steps in some vmware docs (bcdedit /set hypervisorlaunchtype, suboptions under gpedit/DeviceGuard).

When I do disable hyper-v, set hypervisorlaunchtype off, and disable Device Guard, then I get the following options in system info, but then wsl2 fails to launch at all, saying "Please enable the Virtual Machine Platform Windows feature and ensure virtualization is enabled in the BIOS."

Any other configuration I try, sys info says that a hypervisor is running and won't show the hyper-v values, but I end up running into the initial problem of KVM not being supported in WSL2. Also if I try enabling "Virtualize Intel VT-x/EPT" in VMWare Player, that fails to launch as well.

Stepping back, ultimately what I'm trying to do is run the firecracker demo on my windows laptop. So if there's an easier way to do this then lmk.

Update

I noticed it works in VMWare Player with an Ubuntu image. Or at least, kvm-ok reports that it's enabled, /dev/kvm exists. I'd still rather use WSL2. But it's refusing to load.

I have Postgres running on my windows machine and I need to connect to it from inside WSL2.

• The postgres windows service is running
• I can connect to it from the windows command line using psql
• The IP of the WSL2 vm is 172.31.210.120, netmask 255.255.240.0 (determined using ipfconfig).
• The IP of the windows host from inside the vm is 172.31.208.1 (determined using cat /etc/resolv.conf)
• I can connect to a simple web server running on the host from the vm with curl http://172.31.208.1:8080. If I log the IP of the incoming requests, I get 172.31.210.120 so this verifies that both IPs are correct.
• I added the following line to pg_hba.conf: host all all 172.31.210.120/20 scram-sha-256
• I restarted the postgres windows service

If I try to connect to it from WSL using the following command:

$ psql --host=172.31.208.1 --port=5432 --user=postgres

I get this error:

psql: error: could not connect to server: could not connect to server: Connection timed out
        Is the server running on host "172.31.208.1" and accepting
        TCP/IP connections on port 5432?

NOTE: I also tried to test the connection using telnet but it failed too.

The logs under c:\Program Files\PostgreSQL\13\data\log\ show no errors or any signs that there was a connection attempt.

What am I missing here?

I'm having a hard time getting nested virtualization inside my Win10 Pro guest running on KVM host working. Enabling Windows Hypervisor hypervisorlaunchtype auto results in a boot loop/boot to Automatic Repair.

Host:

CentOS Linux release 8.2.2004 (Core)

Intel(R) Xeon(R) E-2176G CPU @ 3.70GHz

# cat /sys/module/kvm_intel/parameters/nested
1

flags       : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx pdpe1gb rdtscp lm constant_tsc art arch_perfmon pebs bts rep_good nopl xtopology nonstop_tsc cpuid aperfmperf tsc_known_freq pni pclmulqdq dtes64 monitor ds_cpl vmx smx est tm2 ssse3 sdbg fma cx16 xtpr pdcm pcid sse4_1 sse4_2 x2apic movbe popcnt tsc_deadline_timer aes xsave avx f16c rdrand lahf_lm abm 3dnowprefetch cpuid_fault invpcid_single pti ssbd ibrs ibpb stibp tpr_shadow vnmi flexpriority ept vpid fsgsbase tsc_adjust bmi1 hle avx2 smep bmi2 erms invpcid rtm mpx rdseed adx smap clflushopt intel_pt xsaveopt xsavec xgetbv1 xsaves dtherm ida arat pln pts hwp hwp_notify hwp_act_window hwp_epp md_clear flush_l1d

Guest:

Microsoft Windows [Version 10.0.19041.508]

I've tried multiple configurations, migrated my Windows from BIOS to UEFI, tried a clean Windows installation, disabled/rebooted/enabled/rebooted the Hypervisor features, etc. nothing working yet.

My current configuration:

  <os>
    <type arch='x86_64' machine='pc-q35-rhel7.6.0'>hvm</type>
    <loader readonly='yes' secure='yes' type='pflash'>/usr/share/OVMF/OVMF_CODE.secboot.fd</loader>
    <nvram>/var/lib/libvirt/qemu/nvram/win10_VARS.fd</nvram>
  </os>
  <features>
    <acpi/>
    <apic eoi='on'/>
    <hyperv>
      <relaxed state='on'/>
      <vapic state='on'/>
      <spinlocks state='on' retries='8191'/>
    </hyperv>
    <kvm>
      <hidden state='on'/>
    </kvm>
    <vmport state='off'/>
    <smm state='on'/>
  </features>
  <cpu mode='host-passthrough' check='partial'>
    <topology sockets='1' cores='4' threads='2'/>
    <feature policy='require' name='ds'/>
    <feature policy='require' name='acpi'/>
    <feature policy='require' name='ss'/>
    <feature policy='require' name='ht'/>
    <feature policy='require' name='tm'/>
    <feature policy='require' name='pbe'/>
    <feature policy='require' name='dtes64'/>
    <feature policy='require' name='monitor'/>
    <feature policy='require' name='ds_cpl'/>
    <feature policy='require' name='vmx'/>
    <feature policy='require' name='smx'/>
    <feature policy='require' name='est'/>
    <feature policy='require' name='tm2'/>
    <feature policy='require' name='xtpr'/>
    <feature policy='require' name='pdcm'/>
    <feature policy='require' name='osxsave'/>
    <feature policy='require' name='tsc_adjust'/>
    <feature policy='require' name='clflushopt'/>
    <feature policy='require' name='intel-pt'/>
    <feature policy='require' name='md-clear'/>
    <feature policy='require' name='stibp'/>
    <feature policy='require' name='ssbd'/>
    <feature policy='require' name='xsaves'/>
    <feature policy='require' name='pdpe1gb'/>
    <feature policy='require' name='invtsc'/>
    <feature policy='disable' name='hypervisor'/>
  </cpu>

Note the last feature hypervisor: If disable, Windows boots and reports Hyper-V as working (systeminfo reports Hyper-V Requirements as available, TaskManager shows Virtualization enabled, etc.), but Hyper-V cannot launch any VM, system logs report that hypervisor is not running. Setting the feature to require brings me in the boot loop/boot to Automatic Repair.

And since it's a bit hard to google this option in this context:

• What does the hypervisor feature exactly do? Where is it documented?

It seems to me that the windows hypervisor crashes on launch with the feature enabled and with the feature disabled just cannot start and continues the boot process.

I'm now out of ideas what else I could try and also believe that I've checked pretty much every search result on the topic. But maybe I've missed something, so please

• Can anyone report a successful setup like this? And if so, sharing the guest config would be great!
• Any other ideas I should try to make this work?

Thanks!

PS: Virtualization itself works great and fast, so I'm pretty sure everything from hardware side is OK, but maybe there're things I should check for as well?!