Add documentation for dns_cached

CONFIG.md

@@ -188,6 +188,22 @@ default: "admin_pass"
 
 Password to access the virtual administrative database
 
+### dns_cache_enabled
+```
+path: general.dns_cache_enabled
+default: false
+```
+When enabled, ip resolutions for server connections specified using hostnames will be cached
+and checked for changes every `dns_max_ttl` seconds. If a change in the host resolution is found
+old ip connections are closed (gracefully) and new connections will start using new ip.
+
+### dns_max_ttl
+```
+path: general.dns_max_ttl
+default: 30
+```
+Specifies how often (in seconds) cached ip addresses for servers are rechecked (see `dns_cache_enabled`).
+
 ## `pools.<pool_name>` Section
 
 ### pool_mode

pgcat.toml

@@ -146,6 +146,14 @@ idle_timeout = 40000
 # Connect timeout can be overwritten in the pool
 connect_timeout = 3000
 
+# When enabled, ip resolutions for server connections specified using hostnames will be cached
+# and checked for changes every `dns_max_ttl` seconds. If a change in the host resolution is found
+# old ip connections are closed (gracefully) and new connections will start using new ip.
+# dns_cache_enabled = false
+
+# Specifies how often (in seconds) cached ip addresses for servers are rechecked (see `dns_cache_enabled`).
+# dns_max_ttl = 30
+
 # User configs are structured as pool.<pool_name>.users.<user_index>
 # This section holds the credentials for users that may connect to this cluster
 [pools.sharded_db.users.0]