add release notes for Embedded Cluster 1.19.0

docs/release-notes/rn-embedded-cluster.md

@@ -10,6 +10,34 @@ This topic contains release notes for the [Replicated Embedded Cluster](/vendor/
 
 Additionally, these release notes list the versions of Kubernetes and Replicated KOTS that are available with each version of Embedded Cluster.
 
+## 1.19.0
+
+Released on November 14, 2024
+
+<table>
+  <tr>
+    <th>Version</th>
+    <td id="center">1.19.0+k8s-1.30</td>
+    <td id="center">1.19.0+k8s-1.29</td>
+  </tr>
+  <tr>
+    <th>Kubernetes Version</th>
+    <td id="center">1.30.5</td>
+    <td id="center">1.29.9</td>
+  </tr>
+  <tr>
+    <th>KOTS Version</th>
+    <td id="center" colspan="2">1.121.0</td>
+  </tr>
+</table>
+
+### New Features {#new-features-1-19-0}
+* Adds preflight checks to ensure that the following kernel parameters are set: `net.ipv4.conf.default.arp_filter = 0`, `net.ipv4.conf.default.arp_ignore = 0`, `net.ipv4.conf.all.arp_filter = 0`, and `net.ipv4.conf.all.arp_ignore = 0`.
+* The following kernel parameters will be written to `/etc/sysctl.d/99-embedded-cluster.conf` and configured automatically during installation: `net.ipv4.ip_forward = 1`, `net.ipv4.conf.default.arp_filter = 0`, `net.ipv4.conf.default.arp_ignore = 0`, `net.ipv4.conf.all.arp_filter = 0`, and `net.ipv4.conf.all.arp_ignore = 0`. An error will not occur if Embedded Cluster fails to set these kernel parameters at install time. Instead, the aforementioned preflight checks will instruct the user to set these parameters.
+
+### Improvements {#improvements-1-19-0}
+* If a user downloads an air gap bundle but attempts to install without it, the user will be instructed how to pass the air gap bundle to `install`. They will then be asked if they want to continue with an online installation anyway.
+
 ## 1.18.0
 
 Released on November 8, 2024