Exam SK0-005 topic 1 question 215 discussion

The MOST likely culprit is: B. The default gateway Why the default gateway? Local users on the same subnet can reach the server directly, so its IP address and subnet mask are probably correct. Remote users (on different networks) need a proper default gateway on the server side (and on their end) to route packets between subnets. If the default gateway is wrong or missing, the server won’t know how to send replies back to remote clients, even though it accepts local connections fine.

local users on the same subnet as the server will still be able to access it without issue because they don’t need to route traffic outside of their local network

If default gateway is wrong local users would most likely have issues.

Outside users are going to have to go through a layer 3 device to get to the server. The router would need to PAT/NAT to server. It doesn’t matter what VLAN the server is on as long as the default gateway is configured correctly at layer 3 for port forwarding to the server.

If the default gateway is wrong, local users would also potentially have issues. If it's just the VLAN that is wrong, local users connected to that VLAN will have access, but no one outside that VLAN can reach the server. So it's more likely that it's a VLAN issue than it is a default gateway issue.