Remote client unable to FTP to my NAS

[glk.asustor@kaup.com]

Hello,

I have turned on the FTP Service on my A6104T NAS. For the time being...
Port: 21
Unicode: Yes
Anonymous: No
SSL/TLS: Yes
FXP: Yes
Max Connections: 12
Max Per IP: 5
Passive FTP Use default port range: YES

I have allowed via both NAT and Firewall...
TCP: 20-21
TCP: 55536-565559

User gets a "connecting message" but the response stops after specifying the server id. There never seems to be a User Name, Password attempt.

I'm obviously missing something... Maybe a port that needs to be opened? SSH? SFTP port?

Any assistance would be greatly appreciated,

[orion]

It could be port 21 still being blocked (some gateways will block low ports by default). You can try to change FTP port to higher one, for example 2121, on both NAS and your gateway. And you need to make sure that you set your ftp client with the matched settings (FTP, no encryption, passive mode).

(I won't transfer files through non-encrypted connection over internet.)

[father.mande]

Hi,

Please try :
check "respond with external I.P. in passive mode" (the Asustor get the external address for you (just wait a second)

As Orion suggest change the port (> 1024)
Also depend of the number of simultaneous passive FTP reduce the range ... to avoid opening port not needed
1 Passive FTP need 1 passive port ... but due to the fact that disconnect sometimes are based in "tcpip keep alive" ... add some more ... to be sure to have enough (if you are alone as client 5 to 10 is large enough)

If nothing work BUT ssh entry works ... move to SFTP (this transfer use only the SSH ... so SSH port and all is encrypted)
ALL descent existing client can use it (filezilla for ex.)
advantage : security + one port already (generally) open
cons. : the client can see all the structure ... so connected as admin ... EVEN solutions exist (like adding a second shh server (Entware apkg) ... so you manage all parameters and users ...

Philippe.

[glk.asustor@kaup.com]

Hello,

Thanks to @orion and @father.mande!

Yes plain insecure FTP is working great... However, now I have a problem with TLS/SSL.

Internal systems are able to FTPS or FTPES just fine, but again, from the outside world I get
a valid connection and all messages down to TLS initiating...

Then it times out! I have not been able to find any logs (yet) to see what else may be going on.
I would really appreciate any information you might have on this... I don't really want to go down
the path of opening up SSH (yet).

Mostly (but not entirely) this is a exercise to learn much more about what I have taken for granted
in terms of managing a linux based server.

Many thanks for all your assistance,
Greg

[orion]

Hello,

Thanks to @orion and @father.mande!

Yes plain insecure FTP is working great... However, now I have a problem with TLS/SSL.

Internal systems are able to FTPS or FTPES just fine, but again, from the outside world I get
a valid connection and all messages down to TLS initiating...

Then it times out! I have not been able to find any logs (yet) to see what else may be going on.
I would really appreciate any information you might have on this... I don't really want to go down
the path of opening up SSH (yet).

Mostly (but not entirely) this is a exercise to learn much more about what I have taken for granted
in terms of managing a linux based server.

Many thanks for all your assistance,
Greg

If you don't want to open another ports in your firewall, you should select "explicit TLS/SSL" in your ftp client on your PC. Of course, you'll need to enable this function in your NAS under ADM -> Services -> Ftp server -> Advanced -> Enable TLS/SSL. That should work.