Add routing peer sizing guide

src/components/NavigationDocs.jsx

@@ -198,6 +198,10 @@ export const docsNavigation = [
             title: 'How Routing Peers Work',
             href: '/manage/networks/how-routing-peers-work',
           },
+          {
+            title: 'Sizing Routing Peers',
+            href: '/manage/networks/sizing-routing-peers',
+          },
           {
             title: 'Masquerade',
             href: '/manage/networks/masquerade',

src/pages/manage/networks/how-routing-peers-work.mdx

@@ -116,6 +116,10 @@ Useful when routing peers are geographically distributed and you want each clien
 
 Place highly available peers in different failure domains within the same network: separate AZs in cloud, separate hypervisors or hosts on-prem.
 
+<Note>
+High availability is failover and nearest-peer selection, not load balancing — it does not spread one network's traffic across its peers. To carry sustained high throughput, see [Sizing Routing Peers](/manage/networks/sizing-routing-peers) for how to size each peer and shard load across multiple Networks.
+</Note>
+
 ## Masquerade
 
 Masquerade is on by default. The routing peer SNATs forwarded traffic to its own LAN-side IP. This is the simplest configuration because the destination network does not need any awareness of NetBird.
@@ -240,6 +244,11 @@ Specifics:
             name: 'Networks',
             description: 'The newer, recommended way to configure routing peers and resources',
         },
+        {
+            href: '/manage/networks/sizing-routing-peers',
+            name: 'Sizing Routing Peers',
+            description: 'Choose the size and number of routing peers from measured throughput',
+        },
         {
             href: '/manage/network-routes',
             name: 'Routes',

src/pages/manage/networks/index.mdx

@@ -77,7 +77,7 @@ Unlike NetBird peers, resources are **not** automatically members of the built-i
 
 A routing peer is a NetBird client installed inside the private network that forwards traffic from the overlay network to devices that don't run the client. Any NetBird client can be one (Linux, Windows, macOS, and others), so the role is about where the machine sits, not which OS it runs. For the full picture, see [How Routing Peers Work](/manage/networks/how-routing-peers-work).
 
-A simple routing peer needs little: 2 vCPUs and 4 GB of RAM is a good baseline, and a small VM or even a Raspberry Pi will do for light use. Scale up as network throughput, link saturation, and the number of users grow.
+A simple routing peer needs little: 2 vCPUs and 4 GB of RAM is a good baseline, and a small VM or even a Raspberry Pi will do for light use. Scale up as network throughput, link saturation, and the number of users grow; [Sizing Routing Peers](/manage/networks/sizing-routing-peers) gives a method for high-throughput deployments.
 
 Because routing peers are usually headless servers, register them with [setup keys](/manage/peers/register-machines-using-setup-keys) instead of interactive login. Setup-key peers aren't subject to [login session expiration](/manage/settings/enforce-periodic-user-authentication), so a routing peer stays connected without periodic re-authentication. That's exactly what an always-on gateway needs. You can assign several routing peers to one Network for high availability; see the [production checklist](#production-checklist).