> ## Documentation Index > Fetch the complete documentation index at: https://docs.gcore.com/llms.txt > Use this file to discover all available pages before exploring further. # Server not responding to ping requests Before troubleshooting, verify that the server is powered on and its status is Active in the [Hosting portal](https://hosting.gcore.com/billmgr). ## The primary IP address does not respond If the OS was installed from a custom ISO image, the network interface must be configured manually — the IP address, subnet mask, and default gateway are not set up automatically. To view the network settings assigned to the server, navigate to **Dedicated servers** in the Hosting portal, select a server, and click **IP addresses**. Dedicated servers list with the IP addresses button highlighted Note the IP address, subnet mask, and default gateway, then configure the network interface in the operating system using the assigned network settings. ## An additional IP address does not respond If the primary IP address is reachable but an additional IP address is not responding to ping, verify that the additional address has been [configured](/hosting/virtual-servers/manage/networking/additional-ip-addresses/configure-an-additional-ip-address) in the operating system. ## The server is unreachable only from China If the server is reachable from other countries but not from China, the IP address may be blocked by the Great Firewall. Use these tools to verify: * [PingChinaz](https://ping.chinaz.com) — shows connectivity status in China only * [ping.pe](https://ping.pe) — shows worldwide connectivity status, including China Due to restrictions imposed by the Great Firewall, connectivity from China cannot be guaranteed. If the IP address is blocked, ordering an [additional IP](/hosting/dedicated-servers/manage/networking/additional-ip-addresses/buy-an-additional-ip-address) usually restores connectivity because blocks typically affect individual IP addresses rather than the entire network.