Why can't I connect to the default port on localhost when using Milvus?

Question

I'm just starting to use Milvus, but cannot connect to the port given in the example. I am running directly on my machine (i.e. not a Docker image), but cannot get initial exampe to work:

$ python
Python 3.10.14 (main, May  6 2024, 19:42:50) [GCC 11.2.0] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> import pymilvus
>>> pymilvus.__version__
'2.4.4'
>>> host="localhost"
>>> port = 19530
>>> from pymilvus import connections
>>> connections.connect("default",host=host,port=port)
Traceback (most recent call last):
  File "/home/me/anaconda3/envs/ShopTalk/lib/python3.10/site-packages/pymilvus/client/grpc_handler.py", line 147, in _wait_for_channel_ready
    grpc.channel_ready_future(self._channel).result(timeout=timeout)
  File "/home/me/anaconda3/envs/ShopTalk/lib/python3.10/site-packages/grpc/_utilities.py", line 162, in result
    self._block(timeout)
  File "/home/me/anaconda3/envs/ShopTalk/lib/python3.10/site-packages/grpc/_utilities.py", line 106, in _block
    raise grpc.FutureTimeoutError()
grpc.FutureTimeoutError

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/home/me/anaconda3/envs/ShopTalk/lib/python3.10/site-packages/pymilvus/orm/connections.py", line 447, in connect
    connect_milvus(**kwargs, user=user, password=password, token=token, db_name=db_name)
  File "/home/me/anaconda3/envs/ShopTalk/lib/python3.10/site-packages/pymilvus/orm/connections.py", line 398, in connect_milvus
    gh._wait_for_channel_ready(timeout=timeout)
  File "/home/me/anaconda3/envs/ShopTalk/lib/python3.10/site-packages/pymilvus/client/grpc_handler.py", line 150, in _wait_for_channel_ready
    raise MilvusException(
pymilvus.exceptions.MilvusException: <MilvusException: (code=2, message=Fail connecting to server on localhost:19530, illegal connection params or server unavailable)>
>>> 

I've tried to guarantee that 19530 is listening:

$ sudo ufw status
Status: active

To                         Action      From
--                         ------      ----
22/tcp                     ALLOW       Anywhere                  
19530/tcp                  ALLOW       Anywhere                  
22/tcp (v6)                ALLOW       Anywhere (v6)             
19530/tcp (v6)             ALLOW       Anywhere (v6)   

But this doesn't seem to make a difference. I suppose there's something `networky' that I'm missing here, but I have no idea what it is. The only installation instructions I saw were 'pip install -U milvus', which I did. What am I not doing here?