The standard Android security system, based on the Linux kernel, by default blocks access to system files for regular applications. The file hostslocated in the /system/etc/directory is responsible for mapping domain names to IP addresses and is a critical element of the device’s network configuration. Traditionally, editing it required obtaining superuser rights (Root), which entails loss of warranty, the risk of “bricking” the smartphone and the inability to use banking applications.
However, modern techniques allow you to bypass these restrictions using legal operating system tools. You can redirect traffic, block ads, or speed up the loading of certain resources without interfering with the integrity of the system partition. This is achieved by using local DNS servers, creating virtual network interfaces, or using ADB debug bridges.
In this guide, we will look at the three most effective ways to modify network rules on your device. We'll look at using specialized applications, setting up private DNS, and working through a computer. Each method has its own characteristics, advantages and limitations that must be taken into account before starting work.
Why standard editing is impossible without Root
Android architecture is built on the principle of isolated processes, where each application runs in its own “sandbox”. The system file is located in a partition that is mounted in read-only mode for all processes that do not have superuser privileges. An application's attempt to write data to this file without the appropriate rights will be immediately rejected by the system kernel. hosts is in the section /system, which is mounted in read-only mode for all processes that do not have superuser privileges. An application's attempt to write data to this file without the appropriate rights will be immediately rejected by the system kernel.
Obtaining Root access essentially removes these restrictions, allowing any application to change any files on the system. However, this action violates the Android security chain of trust. Protection Mechanisms, such as Google SafetyNet and Play Integrity APIs, instantly respond to the presence of root access, blocking payment systems, DRM-protected streaming services and corporate clients.
⚠️ Attention: Receipt Rooting often leads to irreversible activation of Knox counters on Samsung devices or similar protection mechanisms on other brands, which makes it impossible to use some proprietary functions even after returning to the factory state.
That is why workarounds that do not require modification of the system partition become the preferred choice for advanced users. They allow you to flexibly manage network traffic, while maintaining the integrity of the operating system and compatibility with critical software.
Using methods without Root allows you to easily roll back all changes: just uninstall the application or reset the DNS settings, and the system will return to its original state without flashing.
Local DNS server method through applications
The most accessible and popular way to emulate the operation of a file hosts is to use applications that raise a local DNS server on the device. The principle of their operation is that the application does not edit the file itself in the system, but intercepts all DNS requests coming from other apps and processes them according to its own rules.
When your application tries to contact, for example, an advertising server, the local DNS resolver sees this request. If its rule base (analogous to hosts) indicates that this domain should lead to nowhere (to an address 127.0.0.1 or 0.0.0.0), the server returns a false response. As a result, the application cannot establish a connection with the target resource, and the advertisement does not load.
To implement this method, you will need to install specialized software from the Google Play store or third-party repositories. The leaders in this niche are AdGuard, Blokada i PersonalDNSFilter. These tools provide a convenient interface for managing block lists and allow you to import your own rules.
- 🔹 AdGuard: a powerful all-in-one tool that offers not only filtering by hosts, but also deep analysis of HTTPS traffic (with an additional certificate).
- 🔹 Blokada: A lightweight open source solution that focuses specifically on blocking domains based on the hosts file principle.
- 🔹 PersonalDNSFilter: An advanced tool for those who want to create their own DNS server with flexible settings for forwarding rules.
After installing such an application, the system will ask for permission to create a VPN connection. This does not mean that your traffic will be sent to a third party server. On the contrary, a local tunnel is created inside the device through which all DNS traffic passes for filtering.
It is important to understand that this method only works with those requests that use the standard DNS protocol. If an application uses hard-coded IP addresses instead of domain names or uses DNS-over-HTTPS (DoH) technologies bypassing system settings, the efficiency of the local server may decrease.
Setting up private DNS (Private DNS) in Android 9+
Starting with Android 9 (Pie), the system now has native support for the protocol DNS-over-TLS, known as "Private DNS". This feature allows you to redirect all of your device's DNS requests to a trusted server that supports encryption, without the need to install third-party applications.
While this method does not allow you to download arbitrary hosts files directly to your phone, it does allow you to use third-party services that already contain ready-made block lists. You simply provide the address of the service, which acts as a global hosts file for your device. This is the most stable and energy-efficient method.
To configure, go to menu Settings → Connection → Other connection settings → Private DNS. In some shells the path may be different, for example Settings → Network and Internet → Private DNS. Select the “Private DNS Provider Hostname” mode and enter the service address.
| Service | Host address | Main function |
|---|---|---|
| AdGuard DNS | dns.adguard.com |
Blocking ads and trackers |
| Control D | p2.freedns.controld.com |
Blocking malware and advertising |
| NextDNS | your-id.dns.nextdns.io |
Full customization of blocking rules |
| Google DNS | dns.google |
Standard resolution without filtering |
Using the service NextDNS deserves special attention. By registering on their website, you receive a personal address through which you can manage the list of blocked domains in your personal account. Changes made in the web interface are applied to your phone instantly, which is a great alternative to manually editing the file.
⚠️ Attention: When enabling Private DNS, make sure you have a stable internet connection. If the specified server is unavailable, the device may completely lose the ability to resolve domain names, and the Internet will stop working until the settings are changed or rebooted.
This method is ideal for users who want to set up the system once and forget about it. It does not require background applications to run, which has a positive effect on the battery life of the smartphone.
☑️ Checking the operation of Private DNS
Using ADB to temporarily replace hosts
For those who need maximum flexibility and are not afraid of working with the command line, there is a method using Android Debug Bridge (ADB). This tool allows you to send commands to the device from a computer with debugging rights, but without full Root access.
The essence of the method is to launch a local web server or port forwarding, which will intercept requests. However, a more advanced method is to use the command adb shell to temporarily write to memory, although direct writing to /system/etc/hosts without root will still be blocked. Therefore, the "spoofing" technique is more often used by running a process that resolves names differently.
However, there is a working scenario using ADB to install certificates or configurations that affect the network stack. For example, you can force proxy or DNS settings through ADB if the phone interface is blocked or inaccessible.
adb shell settings put global private_dns_mode hostname
adb shell settings put global private_dns_specifier dns.adguard.com
These commands perform the same action as manual configuration in the menu, but allow you to automate the process or configure the device remotely. This is especially useful when mass setting up a fleet of corporate devices.
If you need to test a specific IP address for a domain before implementing it into global settings, you can use ADB to ping. The command adb shell ping will help ensure that the domain resolves to the desired address after applying the DNS settings.
What to do if ADB does not see the device?
Make sure that “USB Debugging” is enabled in the “Developer Options” menu on your phone. Also check whether the ADB driver is installed on the computer and whether you are using the original cable for data transfer, and not just for charging.
Comparison of methods and selection of the optimal solution
The choice of a specific method depends on your goals and level of technical training. Each of the considered options has its own strengths and weaknesses, which determine the scenario for their best use.
Applications with local VPN (AdGuard, Blokada) provide maximum control. You can edit block lists right on your phone, add exceptions for specific applications, and see request statistics. However, they consume additional battery power, since the filtering process occurs constantly in the background.
Setting up Private DNS is the “golden mean”. It does not require the installation of unnecessary software, works at the system level and has virtually no effect on autonomy. The downside is less flexibility: you depend on the capabilities of the selected DNS provider and cannot quickly add one specific domain to the blacklist without registering with a third-party service.
- 🚀 Working speed: Private DNS works the fastest, since it does not create a local VPN tunnel, but uses the system stack.
- 🛡️ Security: All methods are safe to guarantee, but DNS-over-TLS (Private DNS) additionally encrypts your requests, protecting them from being intercepted by your ISP.
- ⚙️ Flexibility: Local applications win by a huge margin, allowing you to fine-tune the rules for yourself.
If your goal is simply to remove advertising in the browser and some applications, just enable dns.adguard.com Private DNS settings. If you are a developer or tester who needs to emulate various network conditions, a combination of ADB and local tools will be indispensable.
For most users, the optimal solution is to use the built-in “Private DNS” function with the address of a reliable filtering service, since this does not require installing additional applications and saves battery.
Common problems and solutions solutions
When setting up network filters, users may encounter a number of typical problems. Understanding the nature of these errors will help you quickly restore the functionality of the Internet.
One of the common problems is the Internet “falling off” after enabling Private DNS. This usually occurs if the host address entered contains a typo or if the selected service is temporarily unavailable. In this case, Android cannot obtain an IP address for any site.
Another problem is blocking not working in specific applications. Some developers use their own DNS implementations or hardcode the IP addresses of ad servers, bypassing system settings. In such cases, only an application with a HTTPS traffic filtering function will help, which requires installing a user certificate.
⚠️ Attention: Settings interfaces may differ depending on the version of Android and the manufacturer’s shell (MIUI, OneUI, ColorOS). If you do not find the “Private DNS” item, use the settings search or enter the service address through an application to change system settings (for example, Activity Launcher), if this is possible without Root.
It is also worth considering that when using local VPN applications, conflicts may arise with other apps that use VPN tunnels (for example, corporate clients or real VPN services for changing the region). Only one VPN tunnel can work at a time.
FAQ: Answers to popular questions
Will the banking application work after setting up DNS?
Yes, using methods without Root, including Private DNS and applications like AdGuard, does not affect the operation of banking applications. Bank security systems respond to the presence of root access and modification of the system partition, and not to network settings.
Is it possible to unblock sites prohibited by the provider in this way?
Partially. If blocking is carried out at the DNS level (which is often done by providers), then changing the DNS server to a foreign one (for example, Cloudflare or Google) will help open the site. If the blocking is based on the IP address (DPI), then simply changing hosts or DNS will not help; you will need a full-fledged VPN or means of bypassing DPI.
Will the Internet speed decrease when using AdGuard or Blokada?
Theoretically, the speed may decrease slightly due to the additional stage of processing requests. In practice, thanks to caching DNS queries and blocking the loading of heavy advertising content, pages often load even faster than without filtering.
How to roll back all changes if the Internet stops working?
The easiest way is to go to the Private DNS settings and select the “Auto” or “Disabled” mode. If you were using an application, simply uninstall it or disable the launch button. As a last resort, rebooting the device into safe mode will help remove the problematic software.
Does this method work on Android 13 and 14?
Yes, all the described methods are fully compatible with the latest versions of Android. The Private DNS feature has been improved in new versions, and filter applications are regularly updated to support new security protocols.