Cisco Umbrella vs DnsServer
Cisco Umbrella and DnsServer are both network ad blocking software. Cisco Umbrella is a commercial product from Cisco. DnsServer is open source under GPL-3.0, with 10k GitHub stars.
Which to pick
- Pick Cisco Umbrella when
- A business or school wants a simple first layer of web filtering and threat blocking across all sites and devices.
- Pick DnsServer when
- You want a full DNS server for your home or office, including authoritative zones, not just a blocker.
Side by side
Cloud DNS-layer security that blocks malicious and unwanted domains for offices and roaming laptops, extending to secure web gateway and firewall features.
A cross-platform authoritative and recursive DNS server with ad blocking, DHCP, encrypted DNS, clustering and a web console.
Higher tiers get expensive and are being folded into Cisco's wider security bundles.
Essentially one developer behind it.
Production-ready (both)
Cloud service
Self-hosted server
Not published
C# and .NET
Closed source, sold by Cisco
Open source, GPL-3.0 (strong copyleft)
Closed source: you use it under the maker's terms and cannot change or resell the code.
Use inside your business is unrestricted, but anything you distribute that includes it must be released under the same license.
No Wikipedia article of its own
10k GitHub stars
Not known
Established: started 9 years ago, latest release v15.6.2.
Other comparisons
More network ad blockers and DNS filters
Both sides were judged on 2026-11-03 from makers' descriptions, Wikipedia, READMEs and GitHub data. License, age and popularity lines are worked out directly.