If you are manually configuring a server through an ISO, or you have misconfigured your current server’s networking, you may be searching for the default gateway, subnet mask, and name servers for IONOS.
Legacy Servers (dedicated and older VPS versions), Cheap Server Deals, AMD and Intel Dedicated Servers on Cloud Panel, and Cloud Servers:
Public IP address: Found in your IONOS control panel or Cloud Panel under Menu > Servers & Cloud.
Subnet Mask: 255.255.255.255
Default Gateway: 10.255.255.1
Preferred DNS Server: 212.227.123.16
Alternate DNS Server: 212.227.123.17
New VPS ordered after May 2023:
Public IP address: Found in your IONOS control panel or Cloud Panel under Menu > Servers & Cloud.
Subnet Mask: 255.255.255.255
Default Gateway: x.x.x.1 [ Replace the first three octets with your server’s Public IP address ]
Preferred DNS Server: 212.227.123.16
Alternate DNS Server: 212.227.123.17
Guides
Adding a Public IPv4 Address to a Dedicated Server (Ubuntu 20.04)
Adding Public IPv4 and IPv6 Addresses on a Linux Server (CentOS Stream 9)
Adding Public IPv4 and IPv6 Addresses on a Linux Server (CentOS Stream 8)
Adding a Public IPv4 Address on a Linux Server (CentOS 7)