Unable to connect when certain DNS servers are configured during cellular communication

[Am4hisa]

Please answer the following questions for yourself before submitting an issue

• [X] Filters were updated before reproducing an issue
• [X] I checked the knowledge base and found no answer
• [X] I checked to make sure that this issue has not already been filed

AdGuard version

4.5.5(1019)

Environment

• OS: 18.0.1
• Device: iphone15 pro

Ad Blocking

AdGuard Base filter, AdGuard Mobile Ads filter

Privacy

AdGuard Tracking Protection filter

Social

AdGuard Social Media filter

Annoyances

AdGuard Cookie Notices filter, AdGuard Popups filter, AdGuard Mobile App Banners filter, AdGuard Other Annoyances filter, AdGuard Widgets filter

Security

No response

Other

No response

Language-specific

AdGuard Japanese filter

Advanced protection for Safari

• [X] yes, I do

Which DNS server do you use?

AdGuard DNS

DNS protocol

DNS-over-HTTPS

Custom DNS

No response

DNS filtering

• [X] yes, I do

Custom DNS filter

https://filters.adtidy.org/dns/filter_1_ios.txt

DNS implementation

AdGuard

Tunnel mode

Full-Tunnel

Low-level settings

Blocked response TTL: 1s Blocking mode: Default Background Apps update: Default

Issue Details

When using cellular communication, selecting Adguard DNS or Cloudflare DNS in the settings prevents the connection. This issue does not occur when using Wi-Fi. I have removed and reconfigured the VPN settings, but the problem persists. I mentioned that I subscribe to the AdGuardDNS filter, but I usually do not use it. Currently, I am subscribed as a workaround since I cannot connect to AdguardDNS due to this issue.

Expected Behavior

Connection should be possible.

Actual Behavior

Connection is not possible.

Screenshots

No response

Additional Information

I have sent the log files and a screen recording of the issue via email.

[maxikuzmin]

@Am4hisa in order to troubleshoot this issue, we need to get your application logs.

Here's what we need you to do:

1. Open Settings -> General -> Turn Advanced mode on -> Advanced settings -> Turn Debug logs switch on.
2. Reproduce the problem, then remember the exact time it happened.
3. Open Settings -> Support -> Export logs.
4. System popup will be opened -> Choose Mail app.
5. Enter qa@adguard.com as a recipient and:
   • include [iOS] keyword and ISSUE_NUMBER in the subject of your email
   • specify the exact time when the issue occurred

[Am4hisa]

@maxikuzmin

As mentioned in the Additional Information section, I sent the logs via email, but are you asking if additional information is needed? Or does this mean that my previous submission did not go through correctly, and I should resubmit?

For now, I have sent the same logs I previously submitted to qa@adguard.com.

[maxikuzmin]

@Am4hisa sorry, but I don't see your logs in email qa@adguard.com. Could you resend the logs? Make sure to include [iOS] keyword and ISSUE_NUMBER in the subject of your email and specify the exact time when the issue occurred

[Am4hisa]

I'm not sure why. The email address domain is @kann.so, and the subject is [iOS] 2383 AdguardForiOS from Am4hisa. I just sent it. 10/23/2024 17:34 (UTC)

I first sent an email to apple@adguard.com. The subject was AdguardTeam/AdguardForiOS Issue #2383, and I sent it on 10/15/2024 at 11:14 (UTC).

The issue happened at 10/15/2024 16:14:09. I think there's a record of this in the log file around that time.

[maxikuzmin]

@Am4hisa it's weird, but I still don't see any emails from you, including I searched by subject and @kann.so and in my spam folder. Please re-check again if you are sending correctly, check your Sent folder, or try sending from another email or app

[Am4hisa]

@maxikuzmin Well, I wonder why that is. Instead of sending an email, I'll write it down below.
Since I cannot reproduce the issue after updating to 4.5.7, I can not provide any further information. Log file: Link have been deleted for privacy reasons. Screen recording: Link have been deleted for privacy reasons. The issue happened at 10/15/2024 16:14:09. I think there's a record of this in the log file around that time.

[maxikuzmin]

@Am4hisa thank you, we'll look at your logs anyway, it'll take us a while

[maxikuzmin]

@Am4hisa we need some more time, please wait

[Am4hisa]

@maxikuzmin

As I mentioned before, I’m not experiencing any issues on my end following the app update, so I’m not facing any problems now. However, if this issue is indeed a bug, I hope the logs and videos I provided will be helpful in resolving it.