# Diagnose YunoHost functioning If you have successfully [installed](/install) YunoHost and passed through the [post-installation](/postinstall), you probably have a **working server**. ### 1. Test it In a web browser, access to your server via the domain name you just entered at the post-installation step. For example: `http://mydomain.com`
If you have taken a .nohost.me or a .noho.st domain, you may have to wait 5 min before the address is reachable.
--- #### If that does not work... --- ### 2. Have you configured your DNS well ?
This step is not necessary if you have a .nohost.me or a .noho.st domain
Go to https://www.whatsmydns.net/ , enter your domain name in the field and click `Search`. If you do not see your IP address, or if there are red crosses everywhere, then you have probably misconfigured your [DNS](/dns). --- ### 3. Are network ports opened on your router ? If your DNS is properly configured, and your server is accessible locally, you may have **network ports blocked** or it may not be forwarded by your router. In order to verify this, try accessing your server with a client outside your local network. For example via another WiFi access point or with your mobile phone in 3G/4G. If the server is unreachable from outside your local network too, then the problem probably comes from your router's configuration.
Try to activate uPnP in your router's configuration interface, and check that your server is plugged in Ethernet directly behind it.

You can also redirect ports manually to your server's local IP address on the router's configuration interface.

--- ### 4. Do your router has hairpinning ? If the server is accessible from outside your local network, but unreachable with its domain name on the local network, then your router probably lacks hairpinning. Here is a [tutorial](dns_local_network) to access your server on a local network and bypass the hairpinning problem. The tutorial proposes a first solution to create a redirection with DNSĀ of the ISP box and a second solution to modify the `hosts` file of the **clients** to instruct it to access the **server** via its local IP address. The first solution is preferable because it's not necessary to modify the `hosts` files on every computer on your local network, if you are using many different clients.