In our iOS networking related app for the app store (with network extension using packet tunnel provider), we are supposed to read the list of nameservers for the network. We use res_ninit function. This function returns only 3 items (but in reality the network has more dns servers. In my case 5. Some ipv4 and some ipv6) Looking at the header file at iOS 18.2 -> user/include/resolve.h, it shows that the __res_state struct has a maximum limit of 3 for the nsaddr_list array. It seems that the reason the res_ninit function returns only 3 values is because of this. For our code to work correctly, it needs to know all the dns servers, but we only get partial results. Is there any other api that can get us all the dns servers ?

Hi, I am trying to create an App which connects to a Device via Wifi and then has to do some HTTP Requests. Connecting to the Wifi is working properly but when I try to make an HTTP API Call I get the response that the Domain is unavailable (No Internet Connection). I created the App in Flutter on Android everything works perfectly. The packages are all iOS Compatible. But in Safari the URL works so it is probably a permission Issue. I have the Following permissions granted: NSAppTransportSecurity NSBonjourServices NSLocalNetworkUsageDescription I even have Multicast Networking When I test the App I get asked to grant the access to local Network which I am granting. I don´t know what I should do next can somebody help? Feel free to ask for more Information

Hello, I'm running into an issue while developing an iOS app that requires local network access. I’m using the latest MacBook Air M4 with macOS sequoia 15.5 and Xcode 16.1. In the iOS Simulator, my app fails to discover devices connected to the same local network. I’ve already added the necessary key to the Info.plist: NSLocalNetworkUsageDescription This app needs access to local network devices. When I run the app on a real device and M2 Chip Macbook's simulators, it works fine for local network permission as expected. However, in the M4 Chip Macbook's Simulator: The app can’t find any devices on the local network Bonjour/mDNS seems not to be working as well I’ve tried the following without success: Restarting Simulator and Mac Resetting network settings in Simulator Confirming app permissions under System Settings > Privacy & Security Has anyone else encountered this issue with the new Xcode/macOS combo? Is local network access just broken in the Simulator for now, or is there a workaround? Thanks in advance!

I am developing an iOS application using NWPathMonitor for network connectivity monitoring. We discovered a reproducible issue where disabling and re-enabling WiFi triggers an unexpected network status sequence. ENVIRONMENT: iOS Version: 17.x Device: iPhone (various models tested) Network Framework: NWPathMonitor from iOS Network framework STEPS TO REPRODUCE: Device connected to WiFi normally Disable WiFi via Settings or Control Center Re-enable WiFi via Settings or Control Center EXPECTED BEHAVIOR: WiFi reconnects and NWPathMonitor reports stable satisfied status ACTUAL BEHAVIOR: T+0s: WiFi re-enables, NWPathMonitor reports path.status = .satisfied T+8s: NWPathMonitor unexpectedly reports path.status = .unsatisfied with unsatisfiedReason = .notAvailable T+9-10s: NWPathMonitor reports path.status = .satisfied again Connection becomes stable afterward NETWORK PATH TIMELINE: T+0s: satisfied (IPv4: true, DNS: false) T+140ms: satisfied (IPv4: true, DNS: true) T+8.0s: unsatisfied (reason: notAvailable, no interfaces available) T+10.0s: satisfied (IPv4: true, DNS: true) KEY OBSERVATIONS: Timing consistency: unsatisfied event always occurs ~8 seconds after reconnection resolution: "Reset Network Settings" eliminates this behavior TECHNICAL QUESTIONS: What causes the 8-second delayed unsatisfied status after WiFi re-enablement? Is this expected behavior that applications should handle? Why does reset network setting in iPhone fix this issue?

Hello, I have a question about developing an iOS app for general public. Can such an app use DNS Proxy Provider? The TN3134: Network Extension provider deployment article states that DNS Proxy Provider has the following restriction: "per-app on managed devices". Does this imply that a DNS Proxy Provider that can be used in a regular iOS App Store app? On the other hand, NEDNSProxyProvider only works with NEAppProxyFlow, is it possible to make it NOT per-app?

Hi everyone, I'm building a health-focused iOS and watchOS app that uses WatchConnectivity to sync real-time heart rate and core body temperature data from iPhone to Apple Watch. While the HealthKit integration works correctly on the iPhone side, I'm facing persistent issues with WatchConnectivity — the data either doesn't arrive on the Watch, or session(_:didReceiveMessage:) never gets triggered. Here's the setup: On iPhone: Using WCSession.default.sendMessage(_:replyHandler:errorHandler:) to send real-time values every few seconds. On Apple Watch: Implemented WCSessionDelegate, and session(_:didReceiveMessage:) is supposed to update the UI. Both apps have WCSession.isSupported() checks, activate the session, and assign delegates correctly. The session state shows isPaired = true and isWatchAppInstalled = true. Bluetooth and Wi-Fi are on, both devices are unlocked and nearby. Despite all this, the Watch never receives messages in real-time. Sometimes, data comes through in bulk much later or not at all. I've double-checked Info.plist configurations and made sure background modes include "Uses Bluetooth LE accessories" and "Background fetch" where appropriate. I would really appreciate guidance on: Best practices for reliable, low-latency message delivery with WatchConnectivity. Debugging steps or sample code to validate message transmission and reception. Any pitfalls related to UI updates from the delegate method. Happy to share further details. Thanks in advance!

Hi~ I implemented network filtering on iOS using NEFilterControlProvider and NEFilterDataProvider. However, I found that their usage is restricted when distributing through the App Store. Does ADEP-based distribution allow the use of NEFilterControlProvider and NEFilterDataProvider? In TN3134, it states that NEPacketTunnelProvider requires MDM. Should I assume that NEFilterControlProvider and NEFilterDataProvider also require MDM in the same way? Thanks

I am creating an application that needs to connect to an Iot device, so i want to make a wifi hotspot with a custom SSID and password and WPA3. Could you please provide an example code in Objective-C to get started?

We are a Layer 3 VPN provider offering a comprehensive SASE (Secure Access Service Edge) solution that includes TLS inspection, threat protection, granular access control, and secure access to private resources. One of the key challenges we face involves TLS inspection. Many mobile applications, especially on iOS, implement certificate pinning, which causes them to fail when TLS inspection is applied. These apps expect connections to be secured with a specific certificate or trusted certificate authority, and inspection disrupts this trust model. On iOS, the current limitation is that the Packet Tunnel Provider extension does not provide visibility into the originating application (i.e., there is no API to obtain the app’s bundle ID or package name associated with a given network connection). Due to this, we are unable to dynamically determine whether TLS inspection should be bypassed for a particular app. While Apple’s Per-App VPN is one possible solution, it introduces a significant drawback: any applications that are excluded from the VPN configuration are entirely outside the VPN tunnel. This means they do not benefit from any of our SASE features — including secure access to internal resources, DNS/web content filtering, or threat detection. This limits the effectiveness of our solution in environments where both inspection and secure access are critical. We would like to understand whether iOS has any current or planned capabilities to associate a network flow (e.g., a 5-tuple: source IP, destination IP, source port, destination port, and protocol) with the originating app. Such a capability would allow us to programmatically identify certificate-pinned apps and selectively disable TLS inspection without excluding them entirely from the VPN, thereby preserving the full set of SASE protections. Is there any guidance or roadmap update from Apple that addresses this use case?

I have an iPhone app which relies heavily on TCP/IP communication in the local network. Therefore, the application starts a server socket and accepts incoming connections. This worked flawlessly for a long time and we had no problems with this. Problem In the last days however, we observed that for some iPhones with the server role other devices cannot connect to the server of our app. The server does not accept incoming connections on the devices IP address and the client times out. Environment Both iPhones (the server and the client) are in the same network with 192.168.1.0 address range and 255.255.255.0 subnet mask. The server has the IP 192.168.1.11 and the client has 192.168.1.22. This is a normal home WiFi network with no special firewall rules. Both devices have mobile data disabled and the "access local network" permission is granted. The server socket is bound to all interfaces (0.0.0.0). More technical symptoms When the server iPhone is in this faulty state, it seems like it somehow has two ip addresses: 192.168.2.123 and 192.168.1.11 The WiFi preferences show the (correct) .1.11 ip address. The Apps however see the (wrong) .2.123 ip address. I cannot explain where the other ip address comes from and why the device thinks it has this ip address. I've collected interface diagnosis information on a faulty iPhone and it listed the following interfaces and IPs: en0 -> 192.168.2.123 lo0 -> 127.0.0.1 pdp_ip0 (cellular) -> 192.0.0.2 pdp_ip1 to pdp_ip6 (cellular) -> -/- ipsec0 to ipsec6 (vpn) -> -/- llw0 (vpn) -> -/- awdl0 -> -/- anpi0 -> -/- ap1 -> -/- XHC0 -> -/- en1 and en2 (wired) -> -/- utun0 to utun2 (vpn) -> -/- The correct ip of the device is not listed anywhere in this list. A reboot helped to temporarily fix this problem. One user reported the same issue again a few hours later after a reboot. Switching off WiFi and reconnecting does not solve the problem. This issue occurred on several iPhones with the following specs: iOS Version 18.1.1, 18.3.1 iPhone 13 Pro, iPhone 13 Pro Max, iPhone 15 Pro The problem must be on the server side as the client can successfully connect to any other device in the same network. Question(s) Where does this second IP come from and why does the server not accept connections to either ip even though it is bound to 0.0.0.0? Are there any iOS system settings which could lead to this problem? (privacy setting, vpn, ...) What could be done to permanently fix this issue?

I have few API's written with URLSession. Will they work in Carrier-constrained network / satellite mode ?

Hello, We have a SwiftUI-based application that runs as a LaunchAgent and communicates with other internal components using Unix domain sockets (UDS). On Sequoia (macOS virtualized environment), when installing the app, we encounter the Local Network Privacy Alert, asking: "Allow [AppName] to find and connect to devices on the local network?" We are not using any actual network communication — only interprocess communication via UDS. Is there a way to prevent this system prompt, either through MDM configuration or by adjusting our socket-related implementation? Here's a brief look at our Swift/NIO usage: class ClientHandler: ChannelInboundHandler { ... public func channelRead(context: ChannelHandlerContext, data: NIOAny) { ... } ... } // init bootstrap. var bootstrap: ClientBootstrap { return ClientBootstrap(group: group) // Also tried to remove the .so_reuseaddr, the prompt was still there. .channelOption(ChannelOptions.socketOption(.so_reuseaddr), value: 1) .channelInitializer { channel in // Add ChannelInboundHandler reader. channel.pipeline.addHandler(ClientHandler()) } } // connect to the UDS. self.bootstrap.connect(unixDomainSocketPath: self.path).whenSuccess { (channel) in .. self.channel = channel } ... ... // Send some data. self.channel?.writeAndFlush(buffer).wait() Any guidance would be greatly appreciated.

i unfortunatly upgraded to Sequoia since then I see when: i select XCode ->Product->run i see Error: No route to host i cannot grant access to local network for XCode i can no longer debug my program as i did with Sonora

Hi everyone, I’m currently developing a macOS app that is distributed via a DMG file on our website. The app includes an App Extension (appex) for Network Extension functionality. I’m wondering if distributing via DMG on the web requires the app extension to be implemented as a System Extension instead of an App Extension. Is it necessary to migrate to System Extension for web-based DMG distribution, or can I continue using App Extension as is? Any insights or recommendations would be greatly appreciated. Thank you!

I am making a USB attached IoT device that follows the Matter approach to connectivity (IP/mDNS/DHCP). I am having conflicts with it as it appears to MacOS as an Ethernet adapter and this is causing it to be assigned as a "default" route, interfering with routing when my Mac is connected to NAT based WiFi. I'd like to be able to hint to MacOS & iPadOS that this is not a routable private network, the subnet should be respected and a default route should not be assigned to it, otherwise the order of the device connection is used by the IP routing tables and I am concerned my non-routable private network will initialize before Wifi and block NAT based internet connectivity. How can I hint to MacOS/iPadOS "this is not a routable private network, this is not a NAT, do not assign me a default route beyond the subnet I have provided you."

Question: What is the standard, most reliable way to manage temporary files associated with a URLSessionDownloadTask that has been terminated abnormally due to a network error or other issues? Details Hello, I'm currently developing a feature to download multiple files concurrently on iOS using URLSessionDownloadTask, and I have a question regarding the lifecycle of the temporary files created during this process. As I understand it, URLSessionDownloadTask stores incoming data in a temporary file within the tmp directory, typically with a name like CFNetworkDownload_*.tmp. In my testing, temporary files are managed correctly in the normal scenario. For instance, when I call the cancel() method on an active downloadTask and then release all references to it, the corresponding temporary file is automatically cleaned up from the tmp directory shortly after. However, the problem occurs when a download is interrupted abnormally due to external factors, such as a lost network connection. In this situation, the urlSession(_:task:didCompleteWithError:) delegate method is called, but the associated temporary file is not deleted and remains in the tmp directory. I've observed a particularly interesting behavior related to this. Immediately after the error occurs, if I check my app's storage usage in the iOS Settings app, the data size appears to have decreased momentarily. However, the tmp file has not actually been deleted, and after a short while, the storage usage is recalculated to include the size of this orphaned temporary file. Since my app does not support resuming interrupted downloads, these leftover files become orphaned and unnecessarily consume storage. Therefore, I want to ensure they are all reliably deleted. With this context, I'd like to ask the community: What is the standard, most reliable way to manage temporary files associated with a URLSessionDownloadTask that has been terminated abnormally due to a network error or other issues? I am wondering if there is an official guide or a framework-level API to handle these orphaned files. I would appreciate any advice from those with experience in this area. Thank you.

We have a Java application built for macOS. On the first launch, the application prompts the user to allow local network access. We've correctly added the NSLocalNetworkUsageDescription key to the Info.plist, and the provided description appears in the system prompt. After the user grants permission, the application can successfully connect to a local server using its hostname. However, the issue arises after the system is rebooted. When the application is launched again, macOS does not prompt for local network access a second time—which is expected, as the permission was already granted. Despite this, the application is unable to connect to the local server. It appears the previously granted permission is being ignored after a reboot. A temporary workaround is to manually toggle the Local Network permission off and back on via System Settings > Privacy & Security, which restores connectivity—until the next reboot. This behavior is highly disruptive, both for us and for a significant number of our users. We can reproduce this on multiple systems... The issues started from macOS Sequoia 15.0 By opening the application bundle using "Show Package Contents," we can launch the application via "JavaAppLauncher" without any issues. Once started, the application is able to connect to our server over the local network. This seems to bypass the granted permissions? "JavaAppLauncher" is also been used in our Info.plist file Removing the following plist in Recovery Mode seems to resolve the issue rm "/Volumes/Macintosh HD/Library/Preferences/com.apple.networkextension.plist" Is this safe to do?

Hi, I am working on a use case where I want to read the wifi signal strength data in the terms of RSSI (Received Signal Strength Indicator) values (or) any other way of representation. when my iPhone is connected to the wifi and Move around the house. Is this use case possible ? If yes, what are all the entitlements that I have to obtain?

Hi everyone, I’ve been working with the NEPacketTunnelProvider class and came across the cancelTunnelWithError() method. The documentation mentions its general purpose but doesn’t provide much clarity on how and when it should be called. From what I’ve gathered in other forum posts, it seems that cancelTunnelWithError() should be called within my own implementation of the stopTunnel() method, but I’m not entirely sure if that’s the correct usage or whether there are specific scenarios where this applies. Here are my specific questions: Is it correct to always call cancelTunnelWithError() in my implementation of stopTunnel()? Are there specific conditions or scenarios where cancelTunnelWithError() is the preferred way to terminate a tunnel session, rather than other termination methods? What does the system do with the error that I pass to cancelTunnelWithError()? Does it have an impact on how the session termination is handled? Are there best practices or common pitfalls to avoid when using cancelTunnelWithError()? Any insights, examples, or guidance would be greatly appreciated! Thanks in advance for your help!

I was having a look through the documentation for NEPacketTunnelProvider, and wanted to know if it's possible for startTunnel(..) and stopTunnel(..) to run simultaneously, and thus require synchronization between resources they deal with? For example, if the VPN is toggled rapidly from system settings, could the setup that occurs in my startTunnel() definition (class instantiation and setTunnelNetworkSettings(value)) potentially occur after the tear-down logic (resource cleanup, setTunnelNetworkSettings(nil)), leaving the system in a state where the VPN is deactivated, but the configuration is in place?