Fix flaky test_dump_cluster_unresponsive_remote_worker (#5679)

Author: crusaderky

distributed/tests/test_utils_test.py

@@ -10,6 +10,8 @@
 import yaml
 from tornado import gen
 
+import dask.config
+
 from distributed import Client, Nanny, Scheduler, Worker, config, default_client
 from distributed.core import Server, rpc
 from distributed.metrics import time
@@ -100,11 +102,8 @@ async def test_gen_cluster_parametrized_variadic_workers(c, s, *workers, foo):
 )
 async def test_gen_cluster_set_config_nanny(c, s, a, b):
     def assert_config():
-        import dask
-
         assert dask.config.get("distributed.comm.timeouts.connect") == "1s"
         assert dask.config.get("new.config.value") == "foo"
-        return dask.config
 
     await c.run(assert_config)
     await c.run_on_scheduler(assert_config)
@@ -535,12 +534,11 @@ async def test_dump_cluster_state_unresponsive_local_worker(s, a, b, tmpdir):
 @gen_cluster(
     client=True,
     Worker=Nanny,
-    config={"distributed.comm.timeouts.connect": "200ms"},
+    config={"distributed.comm.timeouts.connect": "600ms"},
 )
 async def test_dump_cluster_unresponsive_remote_worker(c, s, a, b, tmpdir):
-    addr1, addr2 = s.workers
     clog_fut = asyncio.create_task(
-        c.run(lambda dask_scheduler: dask_scheduler.stop(), workers=[addr1])
+        c.run(lambda dask_scheduler: dask_scheduler.stop(), workers=[a.worker_address])
     )
     await asyncio.sleep(0.2)
 
@@ -549,7 +547,9 @@ async def test_dump_cluster_unresponsive_remote_worker(c, s, a, b, tmpdir):
         out = yaml.safe_load(fh)
 
     assert out.keys() == {"scheduler", "workers", "versions"}
-    assert isinstance(out["workers"][addr2], dict)
-    assert out["workers"][addr1].startswith("OSError('Timed out trying to connect to")
+    assert isinstance(out["workers"][b.worker_address], dict)
+    assert out["workers"][a.worker_address].startswith(
+        "OSError('Timed out trying to connect to"
+    )
 
     clog_fut.cancel()