diff --git a/code/common/service-discovery/src/main/java/nu/marginalia/service/discovery/ZkServiceRegistry.java b/code/common/service-discovery/src/main/java/nu/marginalia/service/discovery/ZkServiceRegistry.java
index a75d1f8d..48efc64f 100644
--- a/code/common/service-discovery/src/main/java/nu/marginalia/service/discovery/ZkServiceRegistry.java
+++ b/code/common/service-discovery/src/main/java/nu/marginalia/service/discovery/ZkServiceRegistry.java
@@ -192,10 +192,18 @@ public class ZkServiceRegistry implements ServiceRegistryIf {
                         .getData()
                         .forPath(ZKPaths.makePath(restRoot, uuid));
                 String hostAndPort = new String(data);
-                ret.add(RestEndpoint
+                var address = RestEndpoint
                         .parse(hostAndPort)
-                        .asInstance(UUID.fromString(uuid))
-                );
+                        .asInstance(UUID.fromString(uuid));
+
+                // Ensure that the address is resolvable
+                // (this reduces the risk of exceptions when trying to connect to the service)
+                if (!address.endpoint().validateHost()) {
+                    logger.warn("Omitting stale address {}, address does not resolve", address);
+                    continue;
+                }
+
+                ret.add(address);
 
             }
 
@@ -221,11 +229,20 @@ public class ZkServiceRegistry implements ServiceRegistryIf {
                 byte[] data = curatorFramework
                         .getData()
                         .forPath(ZKPaths.makePath(restRoot, uuid));
+
                 String hostAndPort = new String(data);
-                ret.add(GrpcEndpoint
+                var address = GrpcEndpoint
                         .parse(hostAndPort)
-                        .asInstance(UUID.fromString(uuid))
-                );
+                        .asInstance(UUID.fromString(uuid));
+
+                // Ensure that the address is resolvable
+                // (this reduces the risk of exceptions when trying to connect to the service)
+                if (!address.endpoint().validateHost()) {
+                    logger.warn("Omitting stale address {}, address does not resolve", address);
+                    continue;
+                }
+
+                ret.add(address);
 
             }
 
diff --git a/code/common/service-discovery/src/main/java/nu/marginalia/service/discovery/property/ServiceEndpoint.java b/code/common/service-discovery/src/main/java/nu/marginalia/service/discovery/property/ServiceEndpoint.java
index e8ce621e..7763eca0 100644
--- a/code/common/service-discovery/src/main/java/nu/marginalia/service/discovery/property/ServiceEndpoint.java
+++ b/code/common/service-discovery/src/main/java/nu/marginalia/service/discovery/property/ServiceEndpoint.java
@@ -3,9 +3,7 @@ package nu.marginalia.service.discovery.property;
 
 import lombok.SneakyThrows;
 
-import java.net.InetSocketAddress;
-import java.net.URI;
-import java.net.URL;
+import java.net.*;
 import java.util.UUID;
 
 public sealed interface ServiceEndpoint {
@@ -17,6 +15,22 @@ public sealed interface ServiceEndpoint {
          return new InetSocketAddress(host(), port());
     }
 
+    /** Validate the host by checking if it is a valid IP address or a hostname that can be resolved.
+     *
+     * @return true if the host is a valid
+     */
+    default boolean validateHost() {
+        try {
+            // Throws UnknownHostException if the host is not a valid IP address or hostname
+            // (this should not be slow since the DNS lookup should be local, and if it isn't;
+            // should be cached by the OS or the JVM)
+            InetAddress.getByName(host());
+            return true;
+        } catch (UnknownHostException e) {
+            return false;
+        }
+    }
+
     static ServiceEndpoint forSchema(ApiSchema schema, String host, int port) {
         return switch (schema) {
             case REST -> new RestEndpoint(host, port);