Robo 3T Error : Network is unreachable

A better solution is to comment out or remove the bindIp setting from the config file /etc/mongod.conf

You must restart the service for the change to take effect

I also meet this problem when I use Robo 3T on Mac. I think there are some things you need to check to help you know what's the problem.

First try to ping the mongo server in your terminal to see whether you can get responses. If so, that's means you may set wrong mongo config in you Robo 3T.

If you cannot get the response, that means there is something wrong with your network. You should check your DNS and your network gateway. For example my DNS is 172.16.* and my network gateway (execute ifconig and check en0) is 172.17.*. And they are not belong to the same network segment. (Actually, even if they are on the same network segment, things won't work if someone polluted your DNS server.)

That's the problem. The DNS that you are using cannot interpret your mongo host correctly. Someone may had polluted this DNS server.

You can have a try on ping xxx(your mongo-server) @8.8.8.8, which will use 8.8.8.8 as your DNS. If everything goes well, then you get the sollution.

Sollution: Manually set DNS for your devices. For example, Google's public DNS, 8.8.8.8 and 8.8.4.4.

Actually, if you run dig xxx(your mongo-server) before and after you manually set DNS, you may find the response Ip differently.

Just change your bind_ip in /etc/mongod.conf from 127.0.0.1 to 0.0.0.0 then restart the service, and it works for me~

If you get the following error then you should also check the following:

The atlas servers at least require this setting, if you do not choose it, then you generally get the Network is unreachable message.

Also if you are using Atlas then you should check the Authentication tab and select SCRAM-SHA-1, however this generally results in an authentication error not a network unreachable one.