As a diagnostic would you ping each of these:
- roborio-6026-frc.local
- roborio-6026-frc.lan
- roborio-6026-frc.frc-robot.local
- The actual IP address assigned to the roboRIO
To get the roboRIO IP address, with the roboRIO connected to the radio , use a PC to connect directly to the roboRIO via a USB cable. Use a web browser (IE or Firefox) to go to 172.22.11.2 and see what Ethernet address was given to the roboRIO. It will be on the front page.