Bug 32852 - WebException: Cannot open passive data connection
Summary: WebException: Cannot open passive data connection
Alias: None
Product: iOS
Classification: Xamarin
Component: BCL Class Libraries ()
Version: XI 8.10
Hardware: PC Mac OS
: --- normal
Target Milestone: Untriaged
Assignee: Bugzilla
Depends on:
Reported: 2015-08-06 23:49 UTC by Frank A. Krueger
Modified: 2015-08-07 00:00 UTC (History)
4 users (show)

Is this bug a regression?: ---
Last known good build:

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Description Frank A. Krueger 2015-08-06 23:49:04 UTC
When trying to download an FTP file on the device:

System.Net.WebException: Cannot open passive data connection


    open System
    let client = new Net.WebClient ()
    let tempPath = IO.Path.GetTempFileName ()
    client.DownloadFile ("ftp://rockyftp.cr.usgs.gov/vdelivery/Datasets/Staged/NED/19/IMG/ned19_n47x75_w122x50_wa_puget_sound_2000.zip", tempPath)

This works on the simulator.

System.Net.WebException: Cannot open passive data connection
at System.Net.FtpWebRequest.SetupPassiveConnection (System.String statusDescription) [0x0017b] in //Library/Frameworks/Xamarin.iOS.framework/Versions/
at System.Net.FtpWebRequest.InitDataConnection () [0x00035] in //Library/Frameworks/Xamarin.iOS.framework/Versions/
at System.Net.FtpWebRequest.OpenDataConnection () [0x00000] in //Library/Frameworks/Xamarin.iOS.framework/Versions/
at System.Net.FtpWebRequest.DownloadData () [0x00007] in //Library/Frameworks/Xamarin.iOS.framework/Versions/
at System.Net.FtpWebRequest.ProcessMethod () [0x001a7] in //Library/Frameworks/Xamarin.iOS.framework/Versions/
at System.Net.FtpWebRequest.ProcessRequest () [0x0002a] in //Library/Frameworks/Xamarin.iOS.framework/Versions/

=== Xamarin Studio ===

Version 5.9.4 (build 5)
Installation UUID: fce13fdd-e8e3-48ef-99f1-4acbb06f0240
	Mono 4.0.2 ((detached/c99aa0c)
	GTK+ 2.24.23 (Raleigh theme)

	Package version: 400020005

=== Xamarin.Android ===

Version: (Enterprise Edition)
Android SDK: /Users/fak/Library/Developer/Xamarin/android-sdk-mac_x86
	Supported Android versions:
		2.3   (API level 10)
		4.0.3 (API level 15)
		4.3   (API level 18)
		4.4   (API level 19)
		5.0   (API level 21)
Java SDK: /usr
java version "1.8.0_20-ea"
Java(TM) SE Runtime Environment (build 1.8.0_20-ea-b23)
Java HotSpot(TM) 64-Bit Server VM (build 25.20-b22, mixed mode)

=== Xamarin Android Player ===

Version: Unknown version
Location: /Applications/Xamarin Android Player.app

=== Apple Developer Tools ===

Xcode 6.4 (7720)
Build 6E35b

=== Xamarin.Mac ===

Version: (Enterprise Edition)

=== Xamarin.iOS ===

Version: (Enterprise Edition)
Hash: 8b265d6
Branch: master
Build date: 2015-06-30 15:19:13-0400

=== Build Information ===

Release ID: 509040005
Git revision: 8010a90f6e246b32364e3fb46ef2c9d1be9c9a2b
Build date: 2015-06-08 16:52:06-04
Xamarin addins: 7e93e9c3503f28770f23ce1b7eafd829919f18e8

=== Operating System ===

Mac OS X 10.10.4
Darwin muon.local 14.4.0 Darwin Kernel Version 14.4.0
    Thu May 28 11:35:04 PDT 2015
    root:xnu-2782.30.5~1/RELEASE_X86_64 x86_64
Comment 1 Frank A. Krueger 2015-08-07 00:00:46 UTC
My apologies - the downloads were just more flaky than on the desktop. It does work if you try enough.