Add load balancing section (#21385)

Author: maxvp

src/content/docs/cloudflare-one/policies/gateway/egress-policies/index.mdx

@@ -8,7 +8,6 @@ sidebar:
 import { Render } from "~/components";
 
 :::note
-
 Only available on Enterprise plans.
 :::
 
@@ -20,6 +19,10 @@ Cloudflare does not publish WARP egress IP ranges. WARP egress IPs are not docum
 
 <Render file="gateway/terraform-precedence-warning" product="cloudflare-one" />
 
+## Load balancing
+
+Gateway traffic that does not match an egress policy will egress from the closest Cloudflare data center with a default Gateway egress IP. If there are two data centers of equal distance from the user, Gateway will split the traffic between the two data centers, and the load balancer will retain the same user selection and egress IP regardless of data center.
+
 ## Force IP version
 
 To control whether only IPv4 or IPv6 is used to egress, ensure you are [filtering DNS traffic](/cloudflare-one/policies/gateway/initial-setup/dns/), then create a DNS policy to [block AAAA or A records](/cloudflare-one/policies/gateway/dns-policies/common-policies/#control-ip-version).