As part of the ongoing upgrades to much of Haverford’s technology infrastructure, the equipment that provides two critical services, DNS and DHCP, will be replaced on August 11.
The Internet, for all it’s wonder, had a modest start. It was developed by people whose frame of reference for communication included good old fashioned telephones. The telephone model was a great example of a system that worked well and reliably. Every telephone had a number, and finding someone’s number meant looking it up in a directory. Computers also needed to communicate, and using some key concepts from this model, the Internet was born. Today, every computer has a “number” (IP Address) and contacting another computer means looking it up in a sort of directory.
The Domain Name System, or DNS, is the service that translates user friendly Internet names (such as www.google.com) to an internet address (such as 188.8.131.52) that computers understand. For example, when you need to call someone you look up their phone number. Likewise, when you enter a web address into a browser the first thing your computer does is look up the website’s Internet “number,” known as its IP Address. The system that computers and other devices at Haverford use to look up IP addresses, and that also provides information to the outside world about Haverford’s IP addresses, is being replaced.
Dynamic Host Configuration Protocol, or DHCP, is the service that hands out IP addresses and tells computers how to reach the DNS directory. When your mobile device, laptop or desktop connects to Haverford’s network it needs an IP address in order to communicate with other computers on the Internet, and it needs to know how to “look up” other computers on the Internet. When a computer first connects, the first thing it does is “call out” asking for this important information. The DHCP system provides that information.
Does This Impact Me?
For most people who use desktops, laptops or mobile devices the change will be transparent. Most won’t need to do anything. When most devices connect to the wired or wireless network they are automatically configured by the DHCP system. On the evening of August 11, please leave your computer turned on. When you return on August 12, please check to see if you can access the Internet. If you can, great! If not, please restart your computer or mobile device. If, after restarting, you still cannot use the Internet, please call ProDesk and we will work with you to resolve any difficulties.
Some equipment, such as file or web servers, specialized scientific equipment with network connections, and some types of printers must be manually configured.
- We have reached out to those we know who manage servers or specialized network-connected equipment and provided them with details on changes they need to make.
- If your equipment is completely managed by IITS, you don’t need to take action. We will be updating all equipment we manage.
Some Additional Technical Notes.
For those making configuration changes to network-connected equipment, here are the details. Please make these changes as soon as possible. IITS has created 2 new DNS addresses for equipment within the 165.82 IP space. The new DNS addresses are:
- These IPs are active and functioning for DNS queries right now.
- These addresses will only respond to NS requests from within the college’s IP space. You cannot use these addresses if your servers are off-campus.
- The new DNS system we’re installing will become authoritative for the college on August 11.
- For a time the old DNS servers will run in parallel to allow time for folks who have not cut over. We will announce a decommission date for the old system sometime after the 11th. After that date, the old DNS addresses, 184.108.40.206, 220.127.116.11 and 18.104.22.168, will be out of service.
- Servers and other equipment not updated to use the new addresses by the decommission date risk losing connectivity to the Internet.