aknight

    Sorry - really weird issue - apologies in advance.

     

    iOS latest 10.2

    Digits installed

     

    Latest T-Mo carrier update installed (today).

     

    Can't reach FTP and other sync-related sites via cellular data.  Works fine over wifi and has worked fine over LTE in the past.

     

    Could be a Digits issue (some sort of virtual network problem??) or a Carrier update issue (they've been disasters in the past) or T-Mo now blocking ports?

     

    How best to resolve?

     

    anybody else seeing this (or not, but using FTP, etc)?

     

    Thx.

      All replies

      • aknight

        Re: FTP and other port blocking??

        Looks like this might be related to a DNS problem - does Digits use a different DNS or set up a different APN on the phone?

          • 0010001100100001

            Re: FTP and other port blocking??

            I don't have Digits but have the same issue. I can connect to my FTP servers fine on wifi, or when on a VPN, but as soon as I try from the T-Mobile cell network it fails immediately.

             

            Same phone connect fine with AT&T sim put in it as well, so it's not a device issue. Would be nice to resolve this.

              • aknight

                Re: FTP and other port blocking??

                ah, so sounds like switching carriers would solve the issue. Sounds like Un-Carrier means un-service maybe.

                • aknight

                  Re: FTP and other port blocking??

                  What os/version/carrier update version are you on?

                   

                  I found problem on iOS 10.2 (and 10.2.1 beta) but not 10.1. Carrier update 27.0 onward.  Unfortunately iOS updates carrier automatically, so can't figure out if it is thet, iOS version, or T-Mo network change combined.

                    • 0010001100100001

                      Re: FTP and other port blocking??

                      Right now I'm on 10.2.1 beta 2 and carrier update 27.1, but this happened for me on 10.2 and with the 27.0 carrier update. Unfortunately I can't roll back to 10.1.x anymore since Apple closed the signing window. To be fair I don't think I've had any of the carrier updates lower than 27.0 because I only recently unlocked the phone and used it on T-Mobile. Has to be something on their end though since it works fine on other networks, on WiFi, and when connected to a VPN...

                       

                      I feel like they're blocking the FTP protocol, because I can connect to the same servers over SSH using Prompt, but can't connect using SFTP through Transmit (I've tried other FTP apps as well, all fail to connect) even though they're using the same ports. I've even changed the server's ports to see if that works, but I still get blocked when trying to connect via SFTP.

                        • aknight

                          Re: FTP and other port blocking??

                          I'm also getting lookup fails on dyndns servers, which is just weird. IP gets to server fine, lookup via name fails. Works fine on VPN over cellular tho.

                           

                          So something beyond just protocol block it seems like. 

                           

                          As I said, weird. And frustrating.

                            • 0010001100100001

                              Re: FTP and other port blocking??

                              Yes, very frustrating. I've tried connecting directly to the IP addresses instead of the domains and that fails as well.

                               

                              Honestly I'm kind of relieved to see I'm not the only one with this issue. Up until I saw this post I haven't seen much proof of this being an issue. It sucks, but at least it's not just me? ¯\_(ツ)_/¯

                                • aknight

                                  Re: FTP and other port blocking??

                                  Yeah, for SFTP, direct IP doesn't work for me either. WebDAV does however work so you could switch (insert all the hassle/issues here).

                                   

                                  Nice to know it isn't just me!

                                   

                                  I re-pinged the TMo Twitter support folks and pointed them to this discussion.

                                   

                                  TMo had a huge fail on iPhone 7 launch where the carrier update was completely borked, so I'm hoping it is some sort of glitch like that vs network change that will never get figured out.

                                   

                                  Will update here if something changes.

                              • 0010001100100001

                                Re: FTP and other port blocking??

                                Just for fun I put the same SIM in an Android phone (Nexus 5 running 6.0.1) and it connects just fine over SSH and SFTP, so this looks like it's specifically an iOS thing

                        • tmo_chris

                          Re: FTP and other port blocking??

                          Hey folks,

                           

                          I saw another post on this issue recently. Deductive reasoning would point to a T-Mobile/iOS issue but other than that other post I saw, this is the only other report I have heard. The best course of action here would be to contact our tech support and have some engineering tickets opened so we can investigate where the failure is happening but it would also help to check things out on the FTP server side to see if it/they are reporting any failures when getting requests from iOS on cellular networks.