Connection impossible any more - How to debug?

[baggeler]

Hello, I have been using Filezilla for quite a long time and now - after some months of pause needed to use again but unable to connect to any server. Everything worked fine some time before but now after update right after start I cant find any configuration that allows me to connect any more...

Im using preconfigured servers to test which worked without problems before - no connection
I increased the timeout to several minutes - same issue.
I deactivated the timeout by using 0 - same issue.

Filezilla is unable to create the connection and cancels de connection after following traced command:

Status: Nächsten Versuch abwarten...
Trace: CControlSocket::SendNextCommand()
Trace: CFtpLogonOpData::Send() in state 0
Status: Auflösen der IP-Adresse für us148.siteground.us
Status: Verbinde mit 146.66.99.115:21...
Status: Verbindung hergestellt, warte auf Willkommensnachricht...
Trace: CFtpControlSocket::OnReceive()
Antwort: 220-#########################################################
Antwort: 220-Please upload your web files to the public_html directory.
Antwort: 220-Note that letters are case sensitive.
Antwort: 220-#########################################################
Antwort: 220 This is a private system - No anonymous login
Trace: CFtpLogonOpData::ParseResponse() in state 1
Trace: CControlSocket::SendNextCommand()
Trace: CFtpLogonOpData::Send() in state 2
Befehl: AUTH TLS
Trace: CRealControlSocket::OnClose(106)
Trace: CFtpControlSocket::ResetOperation(66)
Trace: CControlSocket::ResetOperation(66)
Trace: CFtpLogonOpData::Reset(66) in state 2
Fehler: Herstellen der Verbindung zum Server fehlgeschlagen

Im using same computer as before, same antivirus

What can I do to debug is blocking the connection?
Is there any command sequence to find out the place of issue ?

[baggeler]

BTW the recomended server test by the site mentionned in top topic is POSITIVE and the only warning I found is recarding to IPv6
The entered address does not resolve to an IPv6 address.



Here is the complete server testing result


Status: Resolving address of usm31.siteground.biz

Status: Connecting to 77.104.151.189

Warning: The entered address does not resolve to an IPv6 address.

Status: Connected, waiting for welcome message...

Reply: 220-#########################################################

Reply: 220-Please upload your web files to the public_html directory.

Reply: 220-Note that letters are case sensitive.

Reply: 220-#########################################################

Reply: 220 This is a private system - No anonymous login

Command: CLNT https://ftptest.net on behalf of 189.4.78.216

Reply: 530 You aren't logged in

Command: AUTH TLS

Reply: 234 AUTH TLS OK.

Status: Performing TLS handshake...

Status: TLS handshake successful, verifying certificate...

Status: Received 2 certificates from server.

Status: cert[0]: subject='OU=Domain Control Validated,CN=*.siteground.biz' issuer='C=BE,O=GlobalSign nv-sa,CN=AlphaSSL CA - SHA256 - G2'

Status: cert[1]: subject='C=BE,O=GlobalSign nv-sa,CN=AlphaSSL CA - SHA256 - G2' issuer='OU=GlobalSign Root CA - R3,O=GlobalSign,CN=GlobalSign'

Command: USER orgonit2

Reply: 331 User orgonit2 OK. Password required

Command: PASS ***************

Reply: 230-Your bandwidth usage is restricted

Reply: 230 OK. Current restricted directory is /

Command: SYST

Reply: 215 UNIX Type: L8

Command: FEAT

Reply: 211-Extensions supported:

Reply: EPRT

Reply: IDLE

Reply: MDTM

Reply: SIZE

Reply: MFMT

Reply: REST STREAM

Reply: MLST type*;size*;sizd*;modify*;UNIX.mode*;UNIX.uid*;UNIX.gid*;unique*;

Reply: MLSD

Reply: AUTH TLS

Reply: PBSZ

Reply: PROT

Reply: UTF8

Reply: TVFS

Reply: ESTA

Reply: PASV

Reply: EPSV

Reply: SPSV

Reply: ESTP

Reply: 211 End.

Command: PBSZ 0

Reply: 200 PBSZ=0

Command: PROT P

Reply: 200 Data protection level set to "private"

Command: PWD

Reply: 257 "/" is your current location

Status: Current path is /

Command: TYPE I

Reply: 200 TYPE is now 8-bit binary

Command: PASV

Reply: 227 Entering Passive Mode (77,104,151,189,135,201)

Command: MLSD

Status: Data connection established, performing TLS handshake...

Reply: 150 Accepted data connection

Status: TLS handshake successful, verifying certificate...

Status: Received 2 certificates from server.

Status: cert[0]: subject='OU=Domain Control Validated,CN=*.siteground.biz' issuer='C=BE,O=GlobalSign nv-sa,CN=AlphaSSL CA - SHA256 - G2'

Status: cert[1]: subject='C=BE,O=GlobalSign nv-sa,CN=AlphaSSL CA - SHA256 - G2' issuer='OU=GlobalSign Root CA - R3,O=GlobalSign,CN=GlobalSign'

Status: TLS session of transfer connection has been resumed.

Listing: type=cdir;sizd=4096;modify=20181023063336;UNIX.mode=0711;UNIX.uid=809;UNIX.gid=801;unique=700g5180726; .

Listing: type=pdir;sizd=4096;modify=20181023063336;UNIX.mode=0711;UNIX.uid=809;UNIX.gid=801;unique=700g5180726; ..

Listing: type=dir;sizd=4096;modify=20180119013813;UNIX.mode=0700;UNIX.uid=809;UNIX.gid=801;unique=700g5180729; .AVRestore

Listing: type=dir;sizd=4096;modify=20180731120611;UNIX.mode=0755;UNIX.uid=0;UNIX.gid=0;unique=700g518072b; .SGCache

Listing: type=dir;sizd=4096;modify=20160422144120;UNIX.mode=0755;UNIX.uid=0;UNIX.gid=0;unique=700g518072a; .SGCache.1461336080

Listing: type=dir;sizd=4096;modify=20160719143006;UNIX.mode=0755;UNIX.uid=0;UNIX.gid=0;unique=700g518072c; .SGRestore

Listing: type=dir;sizd=4096;modify=20120710231444;UNIX.mode=0700;UNIX.uid=809;UNIX.gid=801;unique=700g518072d; .attracta

Listing: type=dir;sizd=4096;modify=20150426223939;UNIX.mode=0755;UNIX.uid=809;UNIX.gid=801;unique=700g518072e; .autoupdate

Listing: type=file;size=13065;modify=20180118132627;UNIX.mode=0600;UNIX.uid=809;UNIX.gid=801;unique=700g5180409; .bash_history

Listing: type=file;size=33;modify=20080524210444;UNIX.mode=0644;UNIX.uid=809;UNIX.gid=801;unique=700g51807de; .bash_logout

Reply: 226-Options: -a -l

Reply: 226 58 matches total

Status: Skipped display of 48 listing lines

Status: Success

Results

Your server is working and assorted routers/firewalls have been correctly configured for explicit FTP over TLS as performed by this test. However there have been warnings about compatibility issues, not all users will be able to use your server.

For maximum compatibility, consider resolving these warnings.

[botg]

The log from FileZilla and the log from ftptest.net show different hostnames being used.

[baggeler]

Its same result for ANY of the servers I try to connect, thats the point, and as it did work before on same computer I need to know how to debug...



Anyway, here is the local error debug log for exact the same as the hostname above:


Trace: CControlSocket::SendNextCommand()
Trace: CFtpLogonOpData::Send() in state 0
Status: Auflösen der IP-Adresse für usm31.siteground.biz
Status: Verbinde mit 77.104.151.189:21...
Status: Verbindung hergestellt, warte auf Willkommensnachricht...
Trace: CFtpControlSocket::OnReceive()
Antwort: 220-#########################################################
Antwort: 220-Please upload your web files to the public_html directory.
Antwort: 220-Note that letters are case sensitive.
Antwort: 220-#########################################################
Antwort: 220 This is a private system - No anonymous login
Trace: CFtpLogonOpData::ParseResponse() in state 1
Trace: CControlSocket::SendNextCommand()
Trace: CFtpLogonOpData::Send() in state 2
Befehl: AUTH TLS
Trace: CRealControlSocket::OnClose(106)
Trace: CFtpControlSocket::ResetOperation(66)
Trace: CControlSocket::ResetOperation(66)
Trace: CFtpLogonOpData::Reset(66) in state 2
Fehler: Herstellen der Verbindung zum Server fehlgeschlagen

[boco]

Please check your Antivirus, some are injecting fake TLS certificates into the chain.

[baggeler]

Done - same result

By the way I am using McAfee Suite and it didn properly work before

I am conidering to have a look into the router but have no idea what to look fore or how to have a simple test to verify this ?

[botg]

You could try bypassing your router by plugging your computer directly into your modem.

[baggeler]

Ok, Ive tried this and am getting the same result again.
Thats really strange. So now next would be probably to check the router settings. What should I look for? Any checklist?

BTW - Did anybody ever think of a tool (or implemented directly into Filezilla) which visually checks the required parameters for faster debugging? Just a 5 cents worth of thought or feature suggestion... I guess this would be great for reducing support and debugging time..

[botg]

BTW - Did anybody ever think of a tool (or implemented directly into Filezilla) which visually checks the required parameters for faster debugging? Just a 5 cents worth of thought or feature suggestion... I guess this would be great for reducing support and debugging time..

There's nothing to debug in FileZilla. According to the log it's either some third-party software on your computer or some third-party component on your end of the connection dropping the connection.

[baggeler]

I checked my computer outside of this network and - strange enough - it works fine to connect

So now next would be probably to check the router settings. What should I look for?

[botg]

Try to disable everything that's labeled with buzzwords such as smart, intelligent, helper, stateful, deep and the likes.

[baggeler]

The error was in router, for unknown reasons it was not allowing ftp connection