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Register a host and get a public IP

Register the host

  1. On the host, find the wired interface's MAC address with ip link show <interface>.
  2. Go to getonline.cmu.edu and open "Manage your Network Registrations".
  3. Click "register new devices", which opens "Connect to the Wired Network".
  4. Fill in the form and submit it:
  5. Building: University Center
  6. Hostname: the host's name
  7. Hardware address: the MAC from step 1
  8. Ownership: "This is a departmental device, and should not be associated with my account"
  9. Group: scottylabs
  10. The host now shows up under "Manage your Network Registrations". DHCP gives it a private address, and its name is <host>.lan.local.cmu.edu.

Request a public IP

Email it-help@cmu.edu, cc ops@scottylabs.org, with the MAC and hostname from the registration:

Hi,

ScottyLabs has a device registered with MAC address <mac> and hostname <host>.lan.local.cmu.edu. We're hoping to put a public-facing service on this host. Can we have a public IP for it?

Thanks,
<name>

Switch the host to the public IP

networkctl renew keeps the old lease, so drop it with networkctl reconfigure. This cuts your SSH session, so schedule it with systemd-run and reconnect at the host's new name, <host>.lan.cmu.edu:

systemd-run --on-active=2 networkctl reconfigure <interface>
ssh root@<host>.lan.cmu.edu

Check that ip -4 -br addr show <interface> and curl -4 https://ifconfig.me both show the public IP.

Then set the host's address in cluster.nix to the public IP. If the host runs a Ceph monitor, do all of this before bootstrapping it, since the monitor's address is fixed in the monitor map.