> For the complete documentation index, see [llms.txt](https://nx.docs.scailable.net/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://nx.docs.scailable.net/ai-manager-v6.1.4/support-and-troubleshooting/troubleshooting/os-checks.md).

# OS checks

## Check Internet and DNS Connectivity

The AI Manager requires internet access and a functioning DNS. Follow these steps to verify connectivity on a Linux system:

## Step 1: Test Internet Connectivity

Test internet connectivity by pinging an external server, such as Google's DNS server.

* **Ping an external server:** Run the following command:

  ```bash
  ping -c 4 8.8.8.8
  ```

  This command sends four ICMP echo requests to Google's DNS server. If you receive replies, your internet connection is working.

## Step 2: Verify DNS Functionality

If the network connection is active but DNS issues are suspected, verify that DNS resolution functions correctly.

* **Ping a domain name:** To check if DNS is working, try pinging a domain name:

  ```bash
  ping -c 4 google.com
  ```

  If the domain name resolves to an IP address and you receive replies, your DNS works. If not, you might see an error like "unknown host," indicating a DNS resolution issue.