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javaandroidftpapache-commons-net

Getting "Unable to determine system type - response: 500 Unknow command" when listing files on ESP8266 with Apache Commons Net

I try to connect to FTP server in ESP8266. Connection is successful, but I can't get list of files on the server.

My code is:

FTPClient mFtpClient = new FTPClient();
mFtpClient.setConnectTimeout(10000);
mFtpClient.connect(InetAddress.getByName(ip));
status = mFtpClient.login(userName, pass);
Log.e("isFTPConnected", String.valueOf(status));
if (FTPReply.isPositiveCompletion(mFtpClient.getReplyCode())) {
    mFtpClient.setFileType(FTP.BINARY_FILE_TYPE);
    mFtpClient.enterLocalPassiveMode();
    FTPFile[] mFileArray = mFtpClient.listFiles();
    Log.e("Size", String.valueOf(mFileArray.length));
}

In logical I get the error :

java.io.IOException: Unable to determine system type - response: 500 Unknow command.

I use Apache Commons Net FTP library. So what is wrong in my code? From FileZilla Windows client, I can connect. May be the reason is that in ESP is SPIFF file system? Or another one reason?

Thanks for answers, and interest!

Solution

  • Your server does not support SYST command, that the FTPClient needs to decide how to parse a response of LIST command.

    Solutions are:

    • If your server supports MLSD command, use mlistDir instead of listFiles.
    • Or use System.setProperty to set FTP_SYSTEM_TYPE_DEFAULT or FTP_SYSTEM_TYPE to suggest what directory listing format your server is using.