docs: VPP IPsec remove lcp and netlink configuration (#2243)

* docs: vpp: remove netlink and lcp IPsec options

Removed netlink and lcp options from the VPP IPsec documentation
(dataplane/ipsec.md) as they were removed from the CLI.

Also updated the IPsec configuration page (vpp/configuration/ipsec.md):
- Clarified that the IPsec option can be configured in the VPP
  configuration section
- Removed the netlink rx-buffer-size and lcp ignore-kernel-routes
  options from the configuration example

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

* docs: vpp: fix wording and broken anchor after netlink removal

- Restore "VPN configuration section" wording (was accidentally changed
  to "VPP configuration section", which contradicts the linked page and
  the fact that IPsec tunnels are configured via the ordinary vpn ipsec
  tree, not a VPP-specific section).
- Fix broken anchor in the "disable the kernel routes synchronization"
  link: lcp.md's real anchor is vpp_config_dataplane_lcp_ignore_kernel_routes,
  not vpp-lcp-configuration.
- Remove leftover blank line left after deleting the netlink section.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

* docs: vpp: fix lcp.md link path and wrap long line

- The link target anchor lives in docs/vpp/configuration/dataplane/lcp.md,
  not a sibling docs/vpp/configuration/lcp.md, so the relative path needs
  the dataplane/ prefix.
- Convert to a shortcut reference link to keep the visible line under the
  80-character doc-lint limit; the long URL moves to a reference
  definition at the bottom of the file, suppressed with
  stop/start_vyoslinter per the documented convention for unavoidably
  long lines.

Verified locally with `python3 scripts/doc-linter.py
'["docs/vpp/configuration/ipsec.md"]'` (exit 0, no warnings).

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

* add ignore-kernel-routes.md

---------

Co-authored-by: Claude Sonnet 5 <noreply@anthropic.com>

2 files changed, 7 insertions, 36 deletions

diff --git a/docs/vpp/configuration/dataplane/ipsec.md b/docs/vpp/configuration/dataplane/ipsec.md
index 0a66221f..8135f9aa 100644
--- a/docs/vpp/configuration/dataplane/ipsec.md
+++ b/docs/vpp/configuration/dataplane/ipsec.md
@@ -34,41 +34,9 @@ IPsec tunnels.
 Enabling this option allows VPP to handle IPsec traffic more efficiently by
 offloading processing from the kernel.
 
-### netlink
-
-VPP uses netlink to receive IPsec event messages from the kernel. Proper
-settings of the following parameters are crucial for ensuring that VPP can
-process all such messages:
-
-```{cfgcmd} set vpp settings lcp netlink batch-delay-ms \<milliseconds\>
-```
-
-This parameter specifies the delay in milliseconds between processing
-batch netlink messages.
-
-```{cfgcmd} set vpp settings lcp netlink batch-size \<number\>
-```
-
-This parameter specifies the maximum number of netlink messages to
-process in a single batch.
-
-```{cfgcmd} set vpp settings lcp netlink rx-buffer-size \<number\>
-```
-
-This parameter specifies the size of the receive buffer for netlink
-socket. If you expect to offload many IPsec tunnels or get frequent and
-intensive rekeying, you may need to increase this value.
-
-:::{note}
-IPsec uses the same netlink parameters as LCP, so tuning them
-affects both LCP and IPsec processing.
-:::
-
 ## Potential Issues and Troubleshooting
 
 Improper IPsec configuration can lead to various issues, including:
 
 - Failure to offload IPsec tunnels to VPP
-- Lost IPsec event messages due to insufficient netlink buffer size or
-  batch settings
 - IPsec states or SAs are not synchronized between kernel and VPP
diff --git a/docs/vpp/configuration/ipsec.md b/docs/vpp/configuration/ipsec.md
index 6ec442e3..86ad920c 100644
--- a/docs/vpp/configuration/ipsec.md
+++ b/docs/vpp/configuration/ipsec.md
@@ -166,8 +166,7 @@ set vpn ipsec site-to-site peer peerB vti traffic-selector remote prefix '192.16
 
 set vpp settings interface eth1
 set vpp settings interface eth2
-set vpp settings ipsec netlink rx-buffer-size '32000'
-set vpp settings lcp ignore-kernel-routes
+set vpp settings ignore-kernel-routes
 ```
 
 Where:
@@ -212,7 +211,7 @@ Improper IPsec configuration can lead to various issues, including:
   interfaces to the IPsec peer, they will conflict with the policy routes
   created for the IPsec tunnel in VPP. Consider using policy-based IPSec
   configuration to avoid this or
-  [disable the kernel routes synchronization](lcp.md#vpp-lcp-configuration).
+  [disable the kernel routes synchronization].
 
 - **Unsupported algorithms**
 
@@ -233,4 +232,8 @@ Improper IPsec configuration can lead to various issues, including:
   tunnel:
 
 ```{cfgcmd} set vpn ipsec site-to-site peer \<peer-name\> force-udp-encapsulation
-```
\ No newline at end of file
+```
+
+% stop_vyoslinter
+[disable the kernel routes synchronization]: dataplane/lcp.md#vpp_config_dataplane_lcp_ignore_kernel_routes
+% start_vyoslinter