feat: flip swap mechanism on sagitta — MD as primary, RST as override

Mirror of #1899 (current) and #1900 (circinus) for sagitta. Same logic,
same scripts, per-branch file set.

Changes:
- Rename docs/**/md-<stem>.md to docs/**/<stem>.md (drop md- prefix) for
  all 210 stems previously listed in docs/_swap.txt
- Rename docs/**/<stem>.rst to docs/**/rst-<stem>.rst (add rst- prefix)
  for the same 210 stems
- Repurpose docs/_swap.txt as docs/_rst_overrides.txt; initially empty
- conf.py exclude_patterns flipped: rst-*.rst excluded by default
- conf.py runtime-artifact references updated to _rst_override_state.json
  and _md_exclude.txt
- scripts/swap_sources.py imported from current (post-#1899 rewrite, with
  inverted rename direction)
- scripts/import_myst.py and tests/test_import_myst.py deleted (obsolete)
- tests/test_swap_sources.py imported from current (post-#1899 rewrite)

Side-effect: fixes the same 404 on /en/1.4/ View page source links that
#1899 fixed for /en/rolling/ and #1900 fixed for /en/1.5/.

Per-branch differences vs #1899:
- sagitta has 210 stems vs current's 254 (sagitta has no vpp pages and
  fewer current-only features; cli + installation/cloud/aws are still
  RST-only on sagitta pending the title-level fix follow-up)
- otherwise the script/conf.py/test changes are byte-identical with current

Generated by robots https://vyos.io

1 files changed, 171 insertions, 0 deletions

diff --git a/docs/installation/virtual/libvirt.md b/docs/installation/virtual/libvirt.md
new file mode 100644
index 00000000..5acefd43
--- /dev/null
+++ b/docs/installation/virtual/libvirt.md
@@ -0,0 +1,171 @@
+(libvirt)=
+
+# Running on Libvirt Qemu/KVM
+
+Libvirt is an open-source API, daemon and management tool for managing platform
+virtualization. There are several ways to deploy VyOS on libvirt kvm.
+Use Virt-manager and native CLI. In an example we will be use use 4 gigabytes
+of memory, 2 cores CPU and default network virbr0.
+
+## CLI
+
+### Deploy from ISO
+
+Create VM name `vyos_r1`. You must specify the path to the `ISO` image,
+the disk `qcow2` will be created automatically. The `default` network is
+the virtual network (type Virtio) created by the hypervisor with NAT.
+
+```none
+$ virt-install -n vyos_r1 \
+  --ram 4096 \
+  --vcpus 2 \
+  --cdrom /var/lib/libvirt/images/vyos.iso \
+  --os-type linux \
+  --os-variant debian10 \
+  --network network=default \
+  --graphics vnc \
+  --hvm \
+  --virt-type kvm \
+  --disk path=/var/lib/libvirt/images/vyos_r1.qcow2,bus=virtio,size=8 \
+  --noautoconsole
+```
+
+Connect to VM with command `virsh console vyos_r1`
+
+```none
+$ virsh console vyos_r1
+
+Connected to domain vyos_r1
+Escape character is ^]
+
+vyos login: vyos
+Password:
+
+vyos@vyos:~$ install image
+```
+
+After installation - exit from the console using the key combination
+`Ctrl + ]` and reboot the system.
+
+### Deploy from qcow2
+
+The convenience of using {abbr}`KVM (Kernel-based Virtual Machine)`
+images is that they don't need to be installed.
+Download predefined VyOS.qcow2 image for `KVM`
+
+```none
+curl --url link_to_vyos_kvm.qcow2 --output /var/lib/libvirt/images/vyos_kvm.qcow2
+```
+
+Create VM with `import` qcow2 disk option.
+
+```none
+$ virt-install -n vyos_r2 \
+   --ram 4096 \
+   --vcpus 2 \
+   --os-type linux \
+   --os-variant debian10 \
+   --network network=default \
+   --graphics vnc \
+   --hvm \
+   --virt-type kvm \
+   --disk path=/var/lib/libvirt/images/vyos_kvm.qcow2,bus=virtio \
+   --import \
+   --noautoconsole
+```
+
+Connect to VM with command `virsh console vyos_r2`
+
+```none
+$ virsh console vyos_r2
+
+Connected to domain vyos_r2
+Escape character is ^]
+
+vyos login: vyos
+Password:
+
+vyos@vyos:~$
+```
+
+The system is fully operational.
+
+## Virt-manager
+
+The virt-manager application is a desktop user interface for managing virtual
+machines through libvirt. On the linux open
+{abbr}`VMM (Virtual Machine Manager)`.
+
+(libvirt-virt-manager-iso)=
+
+### Deploy from ISO
+
+1. Open {abbr}`VMM (Virtual Machine Manager)` and Create a new
+   {abbr}`VM (Virtual Machine)`
+2. Choose `Local install media` (ISO)
+
+:::{figure} /_static/images/virt-libvirt-01.png
+:::
+
+3. Choose path to iso vyos.iso. Operating System can be any Debian based.
+
+:::{figure} /_static/images/virt-libvirt-02.png
+:::
+
+4. Choose Memory and CPU
+
+:::{figure} /_static/images/virt-libvirt-03.png
+:::
+
+5. Disk size
+
+:::{figure} /_static/images/virt-libvirt-04.png
+:::
+
+6. Name of VM and network selection
+
+:::{figure} /_static/images/virt-libvirt-05.png
+:::
+
+7. Then you will be taken to the console.
+
+:::{figure} /_static/images/virt-libvirt-06.png
+:::
+
+(libvirt-virt-manager-qcow2)=
+
+### Deploy from qcow2
+
+Download predefined VyOS.qcow2 image for `KVM`
+
+```none
+curl --url link_to_vyos_kvm.qcow2 --output /var/lib/libvirt/images/vyos_kvm.qcow2
+```
+
+1. Open {abbr}`VMM (Virtual Machine Manager)` and Create a new
+   {abbr}`VM (Virtual Machine)`
+2. Choose `Import existing disk` image
+
+:::{figure} /_static/images/virt-libvirt-qc-01.png
+:::
+
+3. Choose the path to the image `vyos_kvm.qcow2` that was previously
+   downloaded . Operation System can be any Debian based.
+
+:::{figure} /_static/images/virt-libvirt-qc-02.png
+:::
+
+4. Choose Memory and CPU
+
+:::{figure} /_static/images/virt-libvirt-03.png
+:::
+
+5. Name of VM and network selection
+
+:::{figure} /_static/images/virt-libvirt-05.png
+:::
+
+6. Then you will be taken to the console.
+
+:::{figure} /_static/images/virt-libvirt-qc-03.png
+:::