gaierror: [Errno 8] nodename 或 servname 提供，或未知（使用 macOS Sierra）

Question

socket.gethostbyname(socket.gethostname()) worked well on OS X El Capitan. However, it's not working now after the Mac updated to macOS Sierra.

Thanks!

import socket
socket.gethostbyname(socket.gethostname())

Traceback (most recent call last):
  File "<pyshell#26>", line 1, in <module>
    socket.gethostbyname(socket.gethostname())
gaierror: [Errno 8] nodename nor servname provided, or not known

Answer 1

There is an answer in OP's comments based on another question, which requires to edit /etc/hosts , ie echo 127.0.0.1 $HOSTNAME >> /etc/hosts .

Alternatively, you can use socket.gethostbyname('localhost') , assuming that localhost is what you need and it is defined in your /etc/hosts .

Answer 2

Same problem tome. I change the code to:

import socket
socket.gethostbyname("")

And it works now.

Answer 3

I had the same problem today (with MacOS Mojave) and was able to fix it using the link that @FBL provided in the comments.

Specifically, I just had to go to System Preferences -> Sharing and enable sharing. (I enabled printer sharing). Then I verified it was working via ping $HOST . Afterwards, I was able to turn sharing back off and everything (both ping $HOST and python -c 'import socket; print socket.gethostbysocketname(socket.gethostname()) ) still worked.

Answer 4

It seems like a python bug? You need to set the hostname & ipv4 , after this, you can fix it.

import socket
hostname = socket.gethostname()
print(hostname)  >> samzong

# make sure do it
!echo "127.0.0.1 samzong" >> /private/etc/hosts

Answer 5

Rather than using the localhost, use the computer name as specified in /etc/hosts.

For example, /etc/host would have something like this:

127.0.0.1 ET02282-MAC.local
127.0.0.1 localhost

And in your connection use "ET02282-MAC.local"

Answer 6

另一个简单的解决方案是转到终端粘贴 sudo nano /etc/hosts 找到您需要的 ip 地址，IPv4 等。添加一个新行，如 190.123.123.3 Yourterminalname.local 它对我有用

Answer 7

I was having the same issue. I was not able to ping localhost.

ping localhost

>> error ping: cannot resolve localhost: Unknown host

I changed my hosts file.

sudo nano /etc/hosts

Add this to the file (use Tab/4 spaces to separate>> 127.0.0.1{tab/4spaces}localhost) Save it and restart the terminal.

127.0.0.1 localhost

To confirm if everything works fine, try pinging your localhost

ping localhost

Answer 8

If you are using Jupyter notebook or not try this

IP4=str(ipaddress.ip_address(8888))
IPAddr = socket.gethostbyname(IP4)

don't forget to import ipaddress & socket

Answer 9

I was having the same issue.

macOS Catalina

Version: 10.15.7

The solution was::

import socket

if env == "PRODUCTION":
    ip_address = socket.gethostbyname(socket.gethostname())
else:
    ip_address = ""

Answer 10

I had the same error, so I used the subprocess command line utility to find the ip address of my machine. The code I used was:

    from sys import platform
    if platform == "linux" or platform == "linux2":
        # linux
        ip = sb.run(["ipconfig", "getifaddr", "en0"], capture_output=True)
        ...
    elif platform == "darwin":
        # OS X
        ip = sb.run(["ipconfig", "getifaddr", "en0"], capture_output=True)
        ...
    elif platform == "win32":
        # Windows...
        ip = sb.run(["ipconfig", "| findstr /i" "ipv4"],capture_output=True)
        ...
    return ip.stdout.decode()

It returns the IPv4 address of my machine and works on Windows, Mac and Linux

Answer 11

If 127.0.0.1 localhost already exists in your /etc/hosts, try to restart MacBook. It helps to me.

Answer 12

Kind of obvious but if you cloned a project that is using an env variable for your port... best to make sure youve actually set up those env variables...