In a valid subnet mask network part is represented with "1" from left side followed and ended by host part "0" - 11111111.11111111.11111111.00000000 (binary form), 255.255.255.0 (dotted-decimal form) or simply "/24" (where 24 represents that subnet network part is 24 bits long). Subnet calculator allows calculation for 255.255.255.254. Host Bits
Windows should complain about the default gateway setting when you configure it with a message similar to this: You can click "Yes" to allow the configuration. Another point, communication between the DCs and hosts should be successful if the devices are in the same subnet. They would not need a default gateway in this situation. Example routing options - Amazon Virtual Private Cloud To enable instances in a private subnet to connect to the internet, you can create a NAT gateway or launch a NAT instance in a public subnet. Then add a route for the private subnet's route table that routes IPv4 internet traffic ( 0.0.0.0/0 ) to the NAT device. Switch command ip default-gateway - Cisco Community
Jun 22, 2020
What is Default Gateway? It allows devices within one network to send information to devices within another network. If you are requesting a certain web page, the traffic is first sent to your default gateway before leaving the local network to reach its intended destination. How to set default gateway Apr 04, 2014 Configuration
Issue with VPN's default gateway and netmask
Subnet Mask Cheat Sheet If you are a network admin like us, this is a little sheet that you will continually need access to. We hope you find it as helpful as we do.