A clearer comparison between DNS test methods
Switch 90DNS Tester 1.0.5 is a homebrew utility for Nintendo Switch that places legacy DNS results beside results from the firmware 23 Async resolver path. This makes it easier to compare the two methods for each tested Nintendo domain.
The new Async path uses the firmware 23 Query and Fetch resolver operations and is explicitly experimental. The project says this part remains under investigation, so an unusual or incomplete Async result should not automatically be treated as proof that DNS blocking is working or failing.
Every returned address is checked
The tester now examines every address returned by a query before reporting a domain as blocked. For legacy results, the blocking addresses are IPv4 127.0.0.1 and 0.0.0.0. The Async IPv6 checks treat ::1 and :: as blocking addresses. If at least one returned address falls outside the relevant blocking values, the result is reported as unblocked.
This distinction is useful because a response can contain more than one address. The application’s summary does not count unknown results as blocked, avoiding a positive result when the resolver did not provide enough information to make that judgment.
More specific outcomes for failed or incomplete tests
Version 1.0.5 separates several conditions that could otherwise be difficult to interpret. The result screen can show offline when no current network IP is available, unresolved when the resolver does not return a successful address result, timeout when the resolver reports a DNS timeout, and error when IPC, event handling, or result parsing fails.
The new event-wait status has a particularly important meaning. It indicates that the completion event did not arrive within two seconds and that no result was fetched. It does not mean the domain is blocked or unblocked. The application therefore keeps this state distinct from both confirmed outcomes and other failures.
On firmware older than 23.0.0, the Async column displays N/A because that resolver path requires firmware 23.0.0 or newer. Legacy testing remains represented separately, so the two methods are not presented as though they have identical firmware requirements.
Results and diagnostics are saved to the SD card
The application saves test results and IPC diagnostics to sdmc:/90dns-test-log.txt. The log includes the console time, firmware version, EventFd, Query, Poll, EventRead, Fetch when ready, and Cancel information. These entries can provide more context when an Async result is inconclusive or an IPC operation reports an error.
The two-second Async event wait applies per domain rather than limiting the entire run to two seconds. Legacy DNS calls and other IPC operations can take additional time. The project also notes that earlier testing produced several Async results followed by event timeouts, while the cause remained unconfirmed; the new status labels and diagnostics make that situation easier to distinguish from a blocked result.
Using the updated application
The 1.0.5 package is distributed as Switch_90DNS_tester-1.0.5.zip. Extract it to the SD card, then launch switch/Switch_90DNS_tester/Switch_90DNS_tester.nro from the Homebrew Menu. Tests begin automatically, and the application keeps its original name.
After a run, press X to retry both the legacy and Async tests, or press B to exit. A result summary appears at the end of the test cycle, while the side-by-side display shows the individual outcome for each tested Nintendo domain.
What the results can and cannot show
A blocked result confirms that the returned addresses for that particular query matched the application’s blocking-address checks. It does not verify that all system traffic is blocked, and it does not guarantee protection from bans. Results from this utility should therefore be read as DNS query observations rather than a complete network-security assessment.
The project is a modified version of Switch 90DNS Tester that retains the original application name. The local modifications are maintained by STHETIX, while the original project was authored by Nexrem and maintained by its contributors. The application is licensed under LGPL-3.0.
Release details
Switch 90DNS Tester 1.0.5 was published on October 11, 2026. This release adds the experimental firmware 23 Query and Fetch testing path, side-by-side legacy and Async output, address-by-address checking, distinct offline and resolver statuses, event-wait handling, saved diagnostics, and an end-of-run summary.
