feat: flip swap mechanism — MD as primary, RST as override (Phase 1)

This is the first of three phases inverting the per-page swap mechanism
so MD becomes the canonical primary and RST becomes the rare override.

Phase 1 — file renames + conf.py exclude_patterns flip only:
- Rename docs/**/md-<stem>.md to docs/**/<stem>.md (drop md- prefix)
  for all 254 stems previously listed in docs/_swap.txt
- Rename docs/**/<stem>.rst to docs/**/rst-<stem>.rst (add rst- prefix)
  for the same 254 stems
- Repurpose docs/_swap.txt as docs/_rst_overrides.txt; initially empty
  comment-only since no pages need the RST fallback right now
- conf.py exclude_patterns flipped: rst-*.rst is now excluded by default
  instead of md-*.md
- conf.py runtime-artifact references updated to _rst_override_state.json
  and _md_exclude.txt (Phase 2 will rewrite swap_sources.py to produce
  these names; for now no swap script runs because overrides list is empty)

Phase 2 (next commit on this branch) will rewrite scripts/swap_sources.py
with inverted rename direction, delete scripts/import_myst.py + tests, and
update tests/test_swap_sources.py for the new semantics.

Phase 3 will be the cleanup pass and ready-for-review flip.

Generated by robots https://vyos.io

1 files changed, 147 insertions, 0 deletions

diff --git a/docs/troubleshooting/connectivity.md b/docs/troubleshooting/connectivity.md
new file mode 100644
index 00000000..a3c95d8c
--- /dev/null
+++ b/docs/troubleshooting/connectivity.md
@@ -0,0 +1,147 @@
+# Connectivity Tests
+
+## Basic Connectivity Tests
+
+Verifying connectivity can be done with the familiar ping and traceroute
+commands. The options for each are shown (the options for each command were
+displayed using the built-in help as described in the {ref}`cli`
+section and are omitted from the output here):
+
+```{opcmd} ping \<destination\>
+
+Send ICMP echo requests to destination host. There are multiple options to
+ping, including VRF support.
+
+:::{code-block} none
+vyos@vyos:~$ ping 10.1.1.1
+Possible completions:
+<Enter>       Execute the current command
+adaptive      Ping options
+allow-broadcast
+audible
+bypass-route
+count
+deadline
+do-not-fragment
+flood
+interface
+interval
+mark
+no-loopback
+numeric
+pattern
+quiet
+record-route
+size
+timestamp
+tos
+ttl
+verbose
+vrf
+:::
+```
+
+```{opcmd} traceroute \<destination\>
+
+Trace path to target.
+
+:::{code-block} none
+vyos@vyos:~$ traceroute
+Possible completions:
+<hostname>    Track network path to specified node
+<x.x.x.x>
+<h:h:h:h:h:h:h:h>
+ipv4          Track network path to <hostname|IPv4 address>
+ipv6          Track network path to <hostname|IPv6 address>
+:::
+```
+
+
+## Advanced Connectivity Tests
+
+```{opcmd} monitor traceroute \<destination\>
+
+However, another helper is available which combines ping and traceroute
+into a single tool. An example of its output is shown:
+
+:::{code-block} none
+vyos@vyos:~$ mtr 10.62.212.12
+
+                           My traceroute  [v0.85]
+vyos (0.0.0.0)
+Keys:  Help   Display mode   Restart statistics   Order of fields   quit
+                                  Packets               Pings
+Host                            Loss%   Snt   Last   Avg  Best  Wrst StDev
+1. 10.11.110.4                   0.0%    34    0.5   0.5   0.4   0.8   0.1
+2. 10.62.255.184                 0.0%    34    1.1   1.0   0.9   1.4   0.1
+3. 10.62.255.71                  0.0%    34    1.4   1.4   1.3   2.0   0.1
+4. 10.62.212.12                  0.0%    34    1.6   1.6   1.6   1.7   0.0
+:::
+
+:::{note}
+The output consumes the screen and will replace your command
+prompt.
+:::
+
+Several options are available for changing the display output. Press h to
+invoke the built in help system. To quit, just press q and you'll be
+returned to the VyOS command prompt.
+```
+
+
+## IPv6 Topology Discovery
+
+IPv6 uses different techniques to discover its Neighbors/topology.
+
+### Router Discovery
+
+```{opcmd} force ipv6-rd interface \<interface\> [address \<ipv6-address\>]
+
+Discover routers via eth0.
+
+Example:
+
+:::{code-block} none
+vyos@vyos:~$ force ipv6-rd interface eth0
+Soliciting ff02::2 (ff02::2) on eth0...
+
+Hop limit                 :           60 (      0x3c)
+Stateful address conf.    :           No
+Stateful other conf.      :           No
+Mobile home agent         :           No
+Router preference         :         high
+Neighbor discovery proxy  :           No
+Router lifetime           :         1800 (0x00000708) seconds
+Reachable time            :  unspecified (0x00000000)
+Retransmit time           :  unspecified (0x00000000)
+ Prefix                   : 240e:fe:8ca7:ea01::/64
+On-link                 :          Yes
+Autonomous address conf.:          Yes
+Valid time              :      2592000 (0x00278d00) seconds
+Pref. time              :        14400 (0x00003840) seconds
+ Prefix                   : fc00:470:f1cd:101::/64
+On-link                 :          Yes
+Autonomous address conf.:          Yes
+Valid time              :      2592000 (0x00278d00) seconds
+Pref. time              :        14400 (0x00003840) seconds
+ Recursive DNS server     : fc00:470:f1cd::ff00
+DNS server lifetime     :          600 (0x00000258) seconds
+ Source link-layer address: 00:98:2B:F8:3F:11
+ from fe80::298:2bff:fef8:3f11
+:::
+```
+
+
+### Neighbor Discovery
+
+```{opcmd} force ipv6-nd interface \<interface\> address \<ipv6-address\>
+
+Example:
+
+:::{code-block} none
+vyos@vyos:~$ force ipv6-nd interface eth0 address fc00:470:f1cd:101::1
+
+Soliciting fc00:470:f1cd:101::1 (fc00:470:f1cd:101::1) on eth0...
+Target link-layer address: 00:98:2B:F8:3F:11 from fc00:470:f1cd:101::1
+:::
+```
\ No newline at end of file