DNS (Domain Name System) servers are the Internet's phone book. DNS points human-readable domain names to computer-routable IP addresses, allowing your computer to find and load resources hosted online.
Libraries need two types of DNS service:
- Selecting public DNS resolvers for your gateway device allows your library's network to find resources online.
- Managing DNS records for your library's domain is essential for your library's website, staff email, and other public-facing resources.
Public DNS Servers
Safe, reliable public DNS servers allow your library's network to find any resource hosted online. Local DNS servers use DNS forwarders to resolve external domain names that are outside the local network. Selecting reliable public DNS servers to use as forwarders is critical to the performance of your local network.
OPLIN subscribes to Cisco Umbrella, which provides DNS security and optional content filtering through public DNS resolvers. Cisco Umbrella's and Quad9's public DNS resolvers block known malicious domains from resolving in your network. Google's public DNS servers are a reliable, performant public DNS source. Reach out to OPLIN Support (support@oplin.ohio.gov) to request a Cisco Umbrella account for your library to manage filtering settings, access security logs, and more:
| Public DNS Servers | |
|---|---|
| 208.67.222.222 | Cisco Umbrella |
| 208.67.220.220 | Cisco Umbrella |
| 9.9.9.9 | Quad9 DNS |
| 149.112.112.112 | Quad9 DNS |
| 8.8.8.8 | Google DNS |
| 8.8.4.4 | Google DNS |
Managed DNS for Library Domains
OPLIN will manage DNS records for public library domains in the State of Ohio's NS free of charge, upon request. If you do not know your domain's registrar or authoritative nameservers, use ICANN's Lookup Tool to view public domain registration information. To ask about delegating your domain's authoritative nameservers to OPLIN or for DNS change requests, email support@oplin.ohio.gov.
All Ohio public libraries may request a free permanent subdomain in the lib.oh.us zone. OPLIN is the delegated manager of the lib.oh.us TLD. To request a lib.oh.us subdomain for your library, please email support@oplin.ohio.gov.
Service objectives:
- Incident Response: OPLIN staff will respond within one hour to DNS-related malfunctions during regular business hours Monday through Friday from 8:00 a.m. to 5:00 p.m., excluding State of Ohio holidays. Contact us through the OPLIN Support site.
- Incident Resolution: OPLIN staff will work collaboratively with the Ohio Office of Information Technology (OIT) toward resolving the incident within 4 business hours of Incident Response.