I am using Tftpd64 as server for transferring file to client.
Now when client request the file then i see below error in log viewer window of Tftpd64.
Connection received from 2a01:7e00:e000:11c:3546:7805:766:7110 on port 61445 [23/06 11:50:44.967]
Read request for file <test.ota>. Mode octet [23/06 11:50:44.967]
OACK: <blksize=1200,timeout=5,> [23/06 11:50:44.967]
Using local port 61801 [23/06 11:50:44.967]
File <test.ota> : error 10054 in system call recv An existing connection was forcibly closed by the remote host. [23/06 11:50:45.131]
Is any one have idea about above error?
Also i disabled the firewall in my PC but still getting same error.
Finally i am able to make Tftpd64 server up and running. I made below changes.
Enabled Windows Firewall.
Create rule for Tftp server (Widnows firewall->Advance settings->Inbound Rules->New Rule) to allow connection and apply rule for domain, public and private.
Related
I configured Gitea to authenticate against an AD server, and I'm receiving the following error:
[...dels/login_source.go:390 LoginViaLDAP()] [E] LDAP Connect error, my.ad.server.address.here:LDAP Result Code 200 "Network Error": read tcp <gitea host ip>:37590-><ad server ip>:389: read: connection reset by peer
What is strange to me is that the number 37590 in the example above always changes at each occurrence. Is it a port number? If true, how can I track it so I can whitelist it at the AD server firewall?
I'm a newbie in Go, so I can't figure out what's happening.
The 37590 that you see is the source port. It is the port that the server will use when replying and helps your computer know which application the response is for. It's normal for that to change on each request.
You are correct in thinking that this is a network problem. The error message "connection reset by peer" means that someone along the line (either a firewall along the path, or the host itself) closed the connection. (a little more detail here)
If it is a firewall that is not allowing you, then you need a rule allowing access from gitea host ip:any to ad server ip:389.
I am using a call to ftp.exe to upload file to a FTP Server.
This program is running since many years and uploads to number of servers, so far without problems.
After one of the receiver servers has been updated, uploads are no longer possible.
This is the command sequence:
open ftp.xxx.de
<user>
<pw>
>230 User logged in, proceed
cd upload
bin
put <filename>
and in response to this the server replies:
501 PORT IP is not the same as 10.100.244.5
150 File Status okay, about to open Connection
That is it, after this the connection is stuck and gets closed after a certain timeout period.
Funny enough, a google search for "PORT IP is not the same as" return exactly one result, which explains that the IP seen by the server is different from the one expected.
Also, when using WinSCP, FileZilla or other FTP utility programs, the connection has no problem and does transfer files just fine.
So, why does this appear and how to solve it?
The ftp.exe uses an old-fashioned active mode command PORT, which requires the client to specify its IP address to which the FTP servers needs to connect back to open a data transfer connection.
If your are behind a firewall or a NAT, the client may not know its external IP address and uses its local network address. This causes troubles. Either the server fails to connect back as it obviously cannot connect to the client's local network. Or the server rejects the PORT command straight away, if the specified IP address does not match the IP address, from which the FTP client connects to the server. This is a security measure as the difference may indicate a man-in-the-middle attack. Your server does the validation. Some servers might be configured to ignore the IP address specified in the PORT command and connect to a known IP address of the client.
Another way to solve this is, if the firewall/NAT can inspect the FTP traffic and seamlessly modify the IP address in the PORT command. This is obviously not happening.
You do not get the problem with WinSCP or FileZilla, as these clients default to the passive FTP mode, which does not have the problem. Also in the active mode these clients can be configured to use the external IP address. FileZilla also supports the modern EPRT command, that does not need to specify the IP address at all (the server uses the known IP address of the client).
See my article about active/passive FTP mode for details.
I do not think there's any way to make it working with the Windows ftp.exe. It neither supports the passive mode, nor can be configured to use the external IP address, nor supports the EPRT command.
So unless you can configure the FTP server not to do the check and connect to the known IP address of the client or configure your firewall/NAT to modify the IP address in the PORT command, you have to use another FTP client.
As you know that WinSCP works, see the guide for converting the Windows ftp.exe script to WinSCP script.
(I'm the author of WinSCP)
I've a problem with my FTP test server. I've installed and configured FileZilla server, It's listening for control connection on port 21, then it can provide passive mode data connection on ports between 50100 and 51100.
I'm trying a local connection 127.0.0.1:21 and retrieve the LIST of files and folders in the root FTP directory.
FileZilla Client: Works
FTP in MS-DOS: Works
TELNET in MS-DOS: Control connection and user authentication OK, then I switch to passive mode, and when I'm trying to retrieve files and folder with the command LIST It respond "Can't open data connection for transfer of "/"".
I've tried setting firewall rules for ports 50100-51100 and the FileZilla server. It's still not working.
You cannot retrieve files over FTP protocol using a Telnet client.
While you can simulate the FTP client by typing FTP commands on a Telnet console, you cannot do file transfers this way. It's because for file transfer you need a separate data transfer connection, what the Telnet client cannot do.
That's why the FTP server fails. In an active mode, it fails to connect back to your client machine, because there's nothing listening. In a passive more, it timeouts waiting for the client to connect to its data port.
I have googled and searched all over but I am still having trouble getting connected to a site using the ftpzilla
I am getting this read out when I try to connect to the server using the network connection wizard
Connecting to probe.filezilla-project.org
Response: 220 FZ router and firewall tester ready
USER FileZilla
Response: 331 Give any password.
PASS 3.9.0.6
Response: 230 logged on.
Checking for correct external IP address
Retrieving external IP address from
http://ip.filezilla-project.org/ip.php
Checking for correct external IP address IP 173.56.114.112
bhd-fg-bbe-bbc
Response: 200 OK
PREP 60010
Response: 200 Using port 60010, data token 1063172065
PORT 173,56,114,112,234,106
Response: 200 PORT command successful
LIST
Response: 150 opening data connection
Response: 503 Failure of data connection.
Server sent unexpected reply.
Connection closed
The weird thing is I only get this error for this particular server and the server I use for my personal site (namecheap.com) gives me no such error. Does anyone know why this may be happening? And please try not to point me to the network configuration wiki because I have read through that and I still am at this point.
PORT 173,56,114,112,234,106
....
Response: 503 Failure of data connection.
...
please try not to point me to the network configuration wiki
You are using active mode, that is the ftp client (FileZilla) waits for a connection from the server. Obviously the server can not connect to the client which indicates that something like a firewall restricts the connection.
Since according to your description this happens only with few servers, you either use only these servers with active mode or these servers are protected by firewalls which do not allow active mode. Have you tried with passive mode?
I had a similar issue connecting and made the following changes and had success.
Go to File>>>Site Manager>>>
For my site, I changed the Encryption to "Only use plain FTP(insecure)" and had success. May you find the same success.
Am trying to upload a file using libcurl in C. Data transmission is getting failed. Below is the log message.
How to fix this issue?
< 250 CWD command successful.
EPSV
Connect data stream passively
< 500 'EPSV': command not understood
disabling EPSV usage
PASV
< 227 Entering Passive Mode (x,x,x,x,193,152).
Trying x.x.x.x... * No route to host
couldn't connect to host
Closing connection #0
Couldn't connect to server
This means that when the FTP server opens a second port for your client to connect to, your client (libcurl) fails to reach it. It is most likely due to a firewall or other network equipment somewhere along the way that blocks your ability to do the request operation.
Alternative reasons could be a wrongly configured ftp server, but if it works for other users, that seems less likely.
Another reason for failure may be that you have an active firewall that doesn't know EPSV and thus gets confused by it and ruins it for you. Try without it by setting CURLOPT_FTP_USE_EPSV to 0.
You can try to the active approach instead (which is what most older style FTP clients do by default), which makes the client ask the server to connect back to you instead. You activate that in libcurl with CURLOPT_FTPPORT. (See the docs for exact details on how to use it.)