Using a Static IP Address on the CS Grad Nets

If you have requested a static IP address and been given one, here is how to use it on the CS networks.

Plug in to the Network

Your IP address is on either the public grad net or the private grad net, depending on what you initially requested. (See Networking at CS - Overview for more information about our networks.) You must plug your system into an appropriate network jack for the network:

  • For public addresses, use even-numbered jacks.
  • For private addresses, use odd-numbered jacks.

If there are insufficient network jacks with the appropriate numbers in your area, please email support@cs.jhu.edu with the numbered jacks available to you and we'll see about getting one of them onto the appropriate network.

Configure Your Computer

With DHCP

If you're using DHCP, which we recommend, and you indicated that use in your request, you should be able to just plug your system into the network and have it work. If your MAC address changes (e.g. you get a new computer or just a new NIC), you'll have to fill out the CS Network IP Address Application again and mark it at the top as a modification of an existing allocation.

With Manual Configuration

If you want to set your system up manually (and we recommend that you use DHCP instead), here's the information you need.

On the Private Grad/Research Net

If you have an address on the private net, use the following settings:

  • IP Address: The address given to you by the CS IT group.
  • Netmask: 255.255.255.0
  • Default Gateway: 10.161.159.1
  • Nameservers: 10.200.1.1 and 10.200.2.2
  • Search Domain: cs.jhu.edu
  • NTP Servers: ntp1.jhu.edu, ntp2.jhu.edu (NTP servers are optional.)

On the Public Grad/Research Net

If you have an address on the public net, use the following settings:

  • IP Address: The address given to you by the CS IT group.
  • Netmask: 255.255.255.0
  • Default Gateway: 128.220.35.1
  • Nameservers: 10.200.1.1 and 10.200.2.2
  • Search Domain: cs.jhu.edu
  • NTP Servers: ntp1.jhu.edu, ntp2.jhu.edu (NTP servers are optional.)

Open Ports on the JHU Firewall (Optional)

If you have a public IP address, you will probably want to have some of its services available to people outside the Hopkins network. To accomplish that, you'll need to follow the instructions in Requesting Open Ports on the JHU Firewall.

When Your Information Changes

If something about the system changes, like its MAC address or your faculty sponsor, please fill out the CS Network IP Address Application again and select "Modify" at the top of the form.

When You're Done with the Address

When you no longer need this IP address, please fill out the CS Network IP Address Application one last time and select "Delete" at the top of the form.

Troubleshooting

If your even-numbered network jack provides a private IP instead of public, or if your odd-numbered network jack provides a public IP instead of private, or you don't seem to have any network activity coming from your network jack, please email support@cs.jhu.edu, and we will investigate further.