feat(swap): import .md files and webp transition from myst/current

Selective import from origin/myst/current (cf9c9b34):
- Add/update 255 .md files (full MyST conversion plus webp ref updates)
- Delete 175 PNG/JPG from docs/_static/images (webp twins already present)
- Delete 5 autotest topology.png (webp twins already present)

Preserved on swap (untouched):
- All .rst files (incremental swap pattern)
- conf.py, _ext/, _include/*.txt, .gitignore
- 115 canary md-*.md files
- 7 superpowers/specs/*.md design docs
- Logos vyos-logo.png / vyos-logo-icon.png (referenced by conf.py)

🤖 Generated by [robots](https://vyos.io)

1 files changed, 87 insertions, 0 deletions

diff --git a/docs/configuration/interfaces/dummy.md b/docs/configuration/interfaces/dummy.md
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+---
+lastproofread: '2026-01-23'
+---
+
+(dummy-interface)=
+
+# Dummy
+
+A dummy interface is a virtual network interface that operates like the
+loopback interface, accepting traffic and routing it back to the local host.
+Unlike the loopback interface, which is limited to one per system and reserved
+for internal system use, multiple dummy interfaces can be created, removed, and
+managed without impacting core operations.
+
+As a software-based interface, the dummy interface does not depend on physical
+link state and remains active as long as the operating system is running.
+
+Dummy interfaces are commonly used in environments with multiple redundant
+uplinks (e.g., a server connected to two different switches), where assigning a
+management IP address to a specific physical interface is risky. If that
+interface fails, the management IP address becomes unreachable.
+
+Assigning the management IP address to a dummy interface and advertising it
+over all available physical links ensures the address remains reachable as long
+as at least one physical path is active.
+
+Dummy interfaces are also used for testing and simulation purposes.
+
+## Configuration
+
+### Common interface configuration
+
+```{cmdincludemd} /_include/interface-address.txt
+:var0: dummy
+:var1: dum0
+```
+
+```{cmdincludemd} /_include/interface-description.txt
+:var0: dummy
+:var1: dum0
+```
+
+```{cmdincludemd} /_include/interface-disable.txt
+:var0: dummy
+:var1: dum0
+```
+
+```{cmdincludemd} /_include/interface-vrf.txt
+:var0: dummy
+:var1: dum0
+```
+
+
+## Operation
+
+```{opcmd} show interfaces dummy
+
+Show brief interface information.
+
+:::{code-block} none
+vyos@vyos:~$ show interfaces dummy
+Codes: S - State, L - Link, u - Up, D - Down, A - Admin Down
+Interface        IP Address                        S/L  Description
+---------        ----------                        ---  -----------
+dum0             172.18.254.201/32                 u/u
+:::
+```
+
+```{opcmd} show interfaces dummy \<interface\>
+
+Show detailed interface information.
+
+:::{code-block} none
+vyos@vyos:~$ show interfaces dummy dum0
+dum0: <BROADCAST,NOARP,UP,LOWER_UP> mtu 1500 qdisc noqueue state UNKNOWN group default qlen 1000
+    link/ether 26:7c:8e:bc:fc:f5 brd ff:ff:ff:ff:ff:ff
+    inet 172.18.254.201/32 scope global dum0
+       valid_lft forever preferred_lft forever
+    inet6 fe80::247c:8eff:febc:fcf5/64 scope link
+       valid_lft forever preferred_lft forever
+
+    RX:  bytes    packets     errors    dropped    overrun      mcast
+             0          0          0          0          0          0
+    TX:  bytes    packets     errors    dropped    carrier collisions
+       1369707       4267          0          0          0          0
+:::
+```
\ No newline at end of file