[router] add ipv6 support across all components (#11219)

sgl-router/py_src/sglang_router/router.py

@@ -30,7 +30,7 @@ class Router:
             - PolicyType.RoundRobin: Distribute requests in round-robin fashion
             - PolicyType.CacheAware: Distribute requests based on cache state and load balance
             - PolicyType.PowerOfTwo: Select best of two random workers based on load (PD mode only)
-        host: Host address to bind the router server. Default: '127.0.0.1'
+        host: Host address to bind the router server. Supports IPv4, IPv6 (e.g., ::, ::1), or 0.0.0.0 for all interfaces. Default: '0.0.0.0'
         port: Port number to bind the router server. Default: 3001
         worker_startup_timeout_secs: Timeout in seconds for worker startup. Default: 300
         worker_startup_check_interval: Interval in seconds between checks for worker initialization. Default: 10

sgl-router/py_src/sglang_router/router_args.py

@@ -10,7 +10,7 @@ logger = logging.getLogger(__name__)
 class RouterArgs:
     # Worker configuration
     worker_urls: List[str] = dataclasses.field(default_factory=list)
-    host: str = "127.0.0.1"
+    host: str = "0.0.0.0"
     port: int = 30000
 
     # PD-specific configuration
@@ -109,7 +109,7 @@ class RouterArgs:
                 "--host",
                 type=str,
                 default=RouterArgs.host,
-                help="Host address to bind the router server",
+                help="Host address to bind the router server. Supports IPv4, IPv6 (e.g., ::, ::1), or 0.0.0.0 for all interfaces",
             )
             parser.add_argument(
                 "--port",
@@ -123,7 +123,7 @@ class RouterArgs:
             type=str,
             nargs="*",
             default=[],
-            help="List of worker URLs (e.g., http://worker1:8000 http://worker2:8000)",
+            help="List of worker URLs. Supports IPv4 and IPv6 addresses (use brackets for IPv6, e.g., http://[::1]:8000 http://192.168.1.1:8000)",
         )
 
         # Routing policy configuration
@@ -299,8 +299,8 @@ class RouterArgs:
         parser.add_argument(
             f"--{prefix}prometheus-host",
             type=str,
-            default="127.0.0.1",
-            help="Host address to bind the Prometheus metrics server",
+            default="0.0.0.0",
+            help="Host address to bind the Prometheus metrics server. Supports IPv4, IPv6 (e.g., ::, ::1), or 0.0.0.0 for all interfaces",
         )
         parser.add_argument(
             f"--{prefix}request-id-headers",