K8s Process manager update (after cluster changes)

config/tests/deep-segments-config.data.xml

@@ -218,6 +218,7 @@
   <ref class="Variable" id="local-env-ers-warning"/>
   <ref class="Variable" id="local-env-ers-error"/>
   <ref class="Variable" id="local-env-ers-fatal"/>
+  <ref class="Variable" id="local-env-connectivity-port"/>
  </rel>
  <rel name="segment" class="Segment" id="segment-0"/>
  <rel name="infrastructure_applications">

config/tests/nestedConfig.data.xml

@@ -209,6 +209,7 @@
   <ref class="Variable" id="local-env-ers-warning"/>
   <ref class="Variable" id="local-env-ers-error"/>
   <ref class="Variable" id="local-env-ers-fatal"/>
+  <ref class="Variable" id="local-env-connectivity-port"/>
  </rel>
  <rel name="segment" class="Segment" id="top-segment"/>
  <rel name="infrastructure_applications">

config/tests/one-controller-config.data.xml

@@ -116,6 +116,7 @@
   <ref class="Variable" id="local-env-ers-warning"/>
   <ref class="Variable" id="local-env-ers-error"/>
   <ref class="Variable" id="local-env-ers-fatal"/>
+  <ref class="Variable" id="local-env-connectivity-port"/>
  </rel>
  <rel name="segment" class="Segment" id="segment-0"/>
  <rel name="infrastructure_applications">

src/drunc/controller/controller_driver.py

@@ -36,7 +36,9 @@ def __init__(self, address: str, token: Token):
         options = [
             ("grpc.keepalive_time_ms", 60000)  # pings the server every 60 seconds
         ]
-        self.channel = grpc.insecure_channel(self.address, options=options)
+        # The 'ipv4:' prefix forces IPv4 resolution, which helps avoid Kubernetes hairpinning issues
+        target_address = f"ipv4:{self.address}"
+        self.channel = grpc.insecure_channel(target_address, options=options)
         self.stub = ControllerStub(self.channel)
         self.token = Token()
         self.token.CopyFrom(token)

src/drunc/controller/interface/shell_utils.py

@@ -1,4 +1,5 @@
 import datetime
+import ipaddress
 import logging
 import os
 import socket
@@ -7,7 +8,7 @@
 from collections.abc import Sequence
 from concurrent.futures import ThreadPoolExecutor
 from dataclasses import dataclass
-from functools import partial
+from functools import lru_cache, partial
 from urllib.parse import urlparse
 
 import click
@@ -113,8 +114,8 @@ def update_endpoint(endpoint: str) -> str:
             ip_address = urlparse(endpoint).hostname
             if not ip_address:
                 return ""
-            hostname, _, _ = socket.gethostbyaddr(ip_address)
-            return endpoint.replace(ip_address, hostname)
+            resolved_host = get_hostname_smart(ip_address)
+            return endpoint.replace(ip_address, resolved_host)
 
         table.add_row(
             prefix + status_response.name,
@@ -709,3 +710,50 @@ def grab_default_value_from_env(argument_name):
     )(cmd)
 
     return cmd, cmd_name
+
+
+@lru_cache(maxsize=1024)
+def is_private_ip(ip_str: str) -> bool:
+    """
+    Checks if an IP address is private (RFC 1918), loopback, or link-local.
+    These IPs will almost never have a public reverse DNS record.
+    """
+    if not ip_str:
+        return True
+    try:
+        ip_obj = ipaddress.ip_address(ip_str)
+        # .is_private = 10.x, 172.16-31.x, 192.168.x
+        # .is_loopback = 127.x.x.x
+        # .is_link_local = 169.254.x.x
+        return ip_obj.is_private or ip_obj.is_loopback or ip_obj.is_link_local
+    except ValueError:
+        # Not 'valid' IP address -> treat as private
+        return True
+
+
+@lru_cache(maxsize=4096)
+def get_hostname_smart(ip_address: str, timeout_seconds: float = 0.2) -> str:
+    """
+    Resolves an IP to a hostname, with optimizations:
+    1. Caches all results.
+    2. Immediately skips private/internal IPs (like K8s).
+    3. Uses a short timeout for public IPs.
+    """
+
+    # If private IP (k8s), don't try to resolve it
+    if is_private_ip(ip_address):
+        return ip_address
+
+    # If public IP, try to resolve it.
+    original_timeout = socket.getdefaulttimeout()
+    try:
+        socket.setdefaulttimeout(timeout_seconds)
+
+        hostname, _, _ = socket.gethostbyaddr(ip_address)
+        return hostname
+
+    except (socket.herror, socket.gaierror, socket.timeout):
+        return ip_address
+
+    finally:
+        socket.setdefaulttimeout(original_timeout)

src/drunc/data/process_manager/k8s.json

@@ -42,7 +42,9 @@
         "checking": {
             "watcher_retry_sleep": 5,
             "pod_status_check_sleep": 1,
-            "host_cache_expiry": 300
+            "host_cache_expiry": 300,
+            "grpc_startup_timeout": 30,
+            "socket_retry_timeout": 1.0
         }
     }
 }