Can't connect to FTP server when I'm connected via hotspot

I am having the exact same problem, on 2 different computers using 2 different operating systems. Nothing has changed on either system, the only thing that has changes is I updated my phone to iOS 17 (now 17.0.1). I am a photojournalist, and often need to upload photos to different news organizations servers. Before the update, everything was fine. Now, I can't access any of my business client's servers even though my computers are on the internet. This is NOT small problem. I need to get these images into their servers as quickly as possible, and not getting them in is a major problem. Last night I covered a HS football game, and could not log into their server and had to email the photos which slows down their process and looks bad on me. Like I said, nothing has changed except for the iOS. The computer sees the server, and attempts to login, but times out. This NEEDS to be fixed!

As I understand it, it is probably not a problem with using ftp, but with finding the server. You said personal - as in it is in your home network? This would explain why you can't reach it.

How are you accessing the server - using an IP address like 192.168.*.*? using a domain name?

If you are trying to access something in your home from outside (and note that even if you are at home, using the phone hotstop you are *outside* your home network) there are a number of things that need to be done in preparation.

Please clarify the above and we can try to give you instructions for making it work.

I spent the majority of my day on the phone yesterday with AppleCare support, and I have come to the conclusion that Apple doesn't care. They were so adamant that there wasn't a problem, and were so adamant on passing the buck to the carrier, the ftp software, anything but admitting that there is an issue. To recap, I have 2 Apple laptops running 2 separate OS systems. Before I upgraded to iOS 17 everything was flawless. After changing to iOS 17, everything went to crap. My computers would connect hardline, or with any wifi, even the free ones at McDonalds without an issue to any ftp site. But the second I try to use my phone's hotspot, it won't connect. Another photographer friend of mine has the exact same issue after updating his phone, so we troubleshooted. I'm on AT&T, he's on Verizon. I use Panic Software's Transmit, he uses FileZilla. He logged into my phone, no connection. I logged into his phone, no connection. Apple Support said to contact the carrier, it must be an issue with them. I did, no problem at all and actually, using my phone and his, I could get on the internet and access email. I just couldn't connect to ANY server. So I called Apple back, told them I spoke with AT&T and there was no issue and gave them the tech support case number from AT&T. So then It magically became an issue with the ftp client. But it is happening on 2 different clients, on 2 different Mac OS's on 2 different carriers. The only common denominator is iOS 17. I truly believe that Apple has a bug in the system, and are doing their best to pass the buck because they don't release faulty operating systems. Well, there are way too many of us having the exact same issue for them to be ignoring it or passing the buck. Come on Apple, there are people that their jobs rely on using their phones as a hotspot to transfer data, and you are letting a lot of people down.

you can try to see if apples support have some idea

Get Support (apple.com)

And or

Contact - Official Apple Support

And or

Contact - How to Contact Us - Apple

Or

Genius Bar Reservation and Apple Support Options - Apple

Tomas009 wrote:

No, it's FTP server at commercial web hosting company, not in my home network. I have more web hostings in various companies and the problem is the same.

I'm trying to connect via domain name, but I've also tried to connect via IP address. Still timeout...

Thank you

Maybe your cell provider's hotspot plan does not include ftp.

Being older than IP networking itself (yes, really), and its pattern of connections is fundamentally incompatible with modern network firewalls, and being wildly insecure, FTP quite often causes issues, and increasingly often simply gets blocked.

To get FTP to work with a firewall, one or both firewalls (on the local network, and in the remote network) must scan the FTP traffic and preemptively open up the second port. The direction of this second connection depends on whether the FTP connection is operating in active or passive mode. But it’ll always run into a firewall, if the firewall isn’t configured to scan FTP traffic.

(This second data connection used by FTP usually uses an ephemeral port selected at run-time, so there’s no way a firewall can predict that without communications with the FTP server or FTP client, which means either opening up the entire ephemeral range, or configuring the FTP server to use a particular sub-range and opening that, or (as is common on middling and higher-spec firewalls) scanning the passing FTP traffic.)

As FTP openly leaks the server credentials in cleartext, the recipient firewall and recipient FTP server need to process and relocate the arriving files too, as the server can otherwise become filled with unwanted or illegal files.

If you need file uploads with your web server, use HTTPS file uploads, or configure and use SFTP.

If you really need FTP, set up a VPN to wrap the connection; that VPN might be L2TP/IPSec, or maybe FTPS.

PS: also learn about Gifar and other types of polyglot files, particularly if you’re exposing potentially untrusted uploaded files.

if it was me then I would try to download a ftp client on the iphone and see if that could connect both in using cellular and by using your home wifi, that would make it obvious if your carrier does not allow data traffic on that port that the ftp server relies on you connecting to.

Tomas009 wrote:

Sorry, but no useful answer yet. Does anybody have an idea? I tried active/passive mode, I also tried to connect via SFTP. But still the same. Connection via home provider is without any problem. But when I want to connect via hotspot from iPhone, connection timeout.

Thank you.

Check with your carrier, as they appear to be blocking both FTP and SFTP.

Tomas009 wrote:

I called with the support of my carrier and they are not blocking FTP. They assured me that if the problem was on their side, the FTP would not work completely. Not even in iOS app. But in my case, FTP in iOS works, but the problem is only with using hotspot. I'm not able to connect to FTP from my MacBook if it's connected via hotspot.

Connect something with network diagnostics into the network connection, and run a port scan, and see which ports are open and active, and see if that matches the expected open-port pattern of your server. iPhone and iPad are bad at network diagnostics, though there are some (increasingly-limited) scanning tools available. macOS, Linux, BSD, Windows, all are better at this task. Poke into TCP 80 via telnet (less desirable) or s_client or such via TCP 443, if there is a web server, and check the server response, too.

And I’d forget I ever saw or even knew about FTP. Each time I might recall knowing about FTP, just review the hilarity that is the connection pattern. If I really, really, really, really wanted FTP, I’d set up a VPN (end-to-end, not the less-than-useful over-hyped first-few-hope VPN stuff) into the server.

Tomas009 wrote:

I need to connect to my webserver via FTP from my MacOS (13.4.1). When I'm connected via home internet provider, everything is OK. But when I connect via hotspot from my iPhone (iOS 17), I can't connect to FTP. The error message is "Connection timeout". The Internet in web browser is working perfectly, but FTP connection doesn't work. I tried several FTP clients (Filezilla, Forklift, ...), but still the same problem. 

A few weeks ago, I used this FTP clients without any problem with hotspot, so maybe it could be related with iOS 17 update. 

Has anyone same problem? Is there any possibility to analyze network settings to find out where could be the problem? I tried to switch off the Firewall on MacOS, but no change...

Thanks.

My internet relies 100% on hotspot connection...

I have had no issues with hotspot on iOS 17.0.1 and FTP connection

my Firewall is ON

My FTP client has been Fetch for over 10 years w/ no issues

https://fetchsoftworks.com/

I would verify your server is up, if not simply try again later. Server issues are beyond your control and typically get resolved pretty fast. You can always contact your Host for any server side known issues before you beat your head against the wall

macOS 13.6

Fetch 5.8.3 (5K1506) Apple Silicon (Web Store) running on macOS 13.5.2 (22G91) English

Launched at 2023-09-23T19:49:28Z, 23/09/23, 21:49 (local)

Expires 08/10/23 T

Connecting to 2.42.xx.xxx port 21 (Mac OS X firewall is allowing connections) (2023-09-23T19:50:37Z)

An FTP connection to “2.42.xx.xxx” could not be opened because the connection timed out. (There might be a problem with your network, or the server might not be responding.)