FTP connection impossible due to unrecognised certificate on fresh installation

Hello to all,

I have configured a new server based on debian 11 bullseye with ISPConfig 3.2.7p1

Everything is working fine. However after installation, there is a problem with ftp connection on the sites due to a certificate problem.

"The server certificate is unknown ..."

#/////////////////////
I followed the procedure "Perfect Server Automated ISPConfig 3 Installation on Debian 10 - 11 and Ubuntu 20.04" ( howtoforge(.)com/ispconfig-autoinstall-debian-ubuntu/ )

Then
cd /tmp
wget ... ISPConfig-3-stable.tar.gz
tar xfz ISPConfig-3-stable.tar.gz
cd ispconfig3_install/install/

php -q update.php

in order to install an ssh key.

 

By default only if you connect to server hostname fqdn would ISPConfig covered by default but connecting with any other websites domain name would not. So did you connect through the former or the latter?

 

It seems so ! #NoobInProgress

I have configured the host as follows

127.0.0.1 localhost.localdomain localhost

::1 localhost ip6-localhost ip6-loopback
ff02::1 ip6-allnodes
ff02::2 ip6-allrouters


127.0.1.1 server.mydomain.com ServerName
127.0.1.1 ServerName ServerName

I can connect to the Ispconfig interface, create the FTP user, but cannot connect in FTP with Filezilla.
This could be due to a wrong configuration of the host file before installation ?

 

ok I check this point, then I redo a clean install

 

After clean re-install of debian 11 and ispconfig with the perfect server script. (without update)
No errors reported
- client creation
- ftp user creation

In Filezilla
same configuration as this one



I try in Forklift 3 too
address provided by OVH
impossible to connect.
server certificat unknow ...

I am following the same FTP process as on another OVH dedicated server for which ispconfig was installed automatically at the install.
There is something I don't understand!

 

The LE SSL certs used is under your server fqdn thus your ip or any other sites domain in the server, is not included. Meaning you should connect only to e.g. example.server.tld if that is your server fqdn.

 

Thank's @ahrasis
It seems to me that this is what I did. ( but I may have misunderstood )

I am using the same address: example.myserver.com as the one I used to log in to the ispconfig interface ( example.myserver.com:8080 )

On my old server I use the IP address and it works. Here nothing goes. neither in FTP, nor in FTP TLS ...
I am blocked by an unrecognized certificate.

I don't understand. #TooNoob

 

From the images you provided, it shows that you are connecting using some IP and not your server FQDN. In any event, check what is advised by @till above.

 

Thanks for your patience
Simple FTP configuration
user and password ok, server address verified
here is what the filezilla console says :

Code:

Status:         Resolving address of xxxx.yyyyy.net
Status:         Connecting to 00.00.00.00:21...
Status:         Connection established, waiting for welcome message...
Status:         Plain FTP is insecure. Please switch to FTP over TLS. o_O
Status:         Logged in
Status:         Retrieving directory listing...
Command:   PWD
Response:    257 "/" is your current location
Command:   TYPE I
Response:    200 TYPE is now 8-bit binary
Command:   PASV
Response:    227 Entering Passive Mode (54,39,104,64,174,94)
Command:   MLSD
Error:           Connection timed out after 20 seconds of inactivity
Error:           Failed to retrieve directory listing

 

That was it!
thank a lot for your help @till and @ahrasis