MFMT command intermittent on FTP

[Ian Clarke]

We are having problems with the MFMT command not working when using FTP. It works some of the time but fails repeatedly on larger files (greater than 1MB). I have updated to the latest version but the problem persists. Using Filezilla to issue the MFMT on the same file works instantly every time.

Once the MFMT command fails, even PASV commands fail until Bestsync moves on to the next file and then communication is restored.

Extract from transfer log showing the problem:

>FEAT
<211-Extensions supported:
< EPRT
< IDLE
< MDTM
< SIZE
< MFMT
< REST STREAM
< MLST type*;size*;sizd*;modify*;UNIX.mode*;UNIX.uid*;UNIX.gid*;unique*;
< MLSD
< AUTH TLS
< PBSZ
< PROT
< UTF8
< TVFS
< ESTA
< PASV
< EPSV
< SPSV
< ESTP
<211 End.
>OPTS UTF8 ON
<200 OK, UTF-8 enabled
/CS043_Calibration/TestDefs/PendingRelease/ClsCert_LFE old.DAT
>CWD /CS043_Calibration/TestDefs/PendingRelease
<250 OK. Current directory is /CS043_Calibration/TestDefs/PendingRelease
>PASV
<227 Entering Passive Mode (69,90,66,200,177,95)
>RETR ClsCert_LFE old.DAT
<150-Accepted data connection
<150 1905.0 kbytes to download
<226-File successfully transferred
<226 1.249 seconds (measured here), 1.49 Mbytes per second
>PASV
<227 Entering Passive Mode (69,90,66,200,23,100)
>RETR ClsCert_LFE old.DAT
<150-Accepted data connection
<150 1905.0 kbytes to download
<226-File successfully transferred
<226 1.258 seconds (measured here), 1.48 Mbytes per second
/CS043_Calibration/TestDefs/PendingRelease/ClsCert_LFE old.DAT
>PASV
<227 Entering Passive Mode (69,90,66,200,157,76)
>STOR ClsCert_LFE old.DAT
<150 Accepted data connection
>MFMT 20161116103457 ClsCert_LFE old.DAT
<500 Unknown command
>PASV
<500 Unknown command
>PASV
<500 Unknown command
>PASV
<500 Unknown command
>PASV
<500 Unknown command
<<226-File successfully transferred
<<226 20.791 seconds (measured here), 91.63 Kbytes per second
>PASV
<227 Entering Passive Mode (69,90,66,200,139,197)
>RETR ClsCert_LFE old.DAT
<150-Accepted data connection
<150 1905.0 kbytes to download
<226-File successfully transferred

[RiseFly]

It seems that your FTP server has problem when processing MFMT command if the file name contains blank-space.
Please try a file name that does not contain blank-space to see if the problem can be avoided.

[Ian Clarke]

The file did not have a blank space.

I have run a test using a big file (1.8MB) and small file (7 bytes). Again, the log shows that after the MFMT command for the big file, things go wrong but the small file is fine.

Is there a more detailed log that I can get to which might help identify what is going wrong?

We have been using Bestsync for about 5 years and this problem has only started with recent versions.


Log:
>OPTS UTF8 ON
<200 OK, UTF-8 enabled
>CWD /
<250 OK. Current directory is /
>MKD Temp
<257 "Temp" : The directory was successfully created
>CWD /
<250 OK. Current directory is /
>MFMT 20161128142959 Temp
<213 UTIME OK
/Temp/TempBig.DAT
>CWD /Temp
<250 OK. Current directory is /Temp
>PASV
<227 Entering Passive Mode (69,90,66,200,99,191)
>STOR TempBig.DAT
<150 Accepted data connection
>MFMT 20161116103457 TempBig.DAT
<500 Unknown command
>PASV
<500 Unknown command
>PASV
<500 Unknown command
>PASV
<500 Unknown command
>PASV
<500 Unknown command
>PASV
<500 Unknown command
/Temp/TempSmall.DAT
<<226-File successfully transferred
<<226 39.835 seconds (measured here), 47.82 Kbytes per second
>PASV
<227 Entering Passive Mode (69,90,66,200,58,172)
>STOR TempSmall.DAT
<150 Accepted data connection
<226-File successfully transferred
<226 0.106 seconds (measured here), 65.97 bytes per second
>MFMT 20161116170622 TempSmall.DAT
<213 UTIME OK
>PASV
<227 Entering Passive Mode (69,90,66,200,56,214)
>RETR TempSmall.DAT
<150 Accepted data connection
<226-File successfully transferred
<226 0.000 seconds (measured here), 39.55 Kbytes per second
>CWD /
<250 OK. Current directory is /
>MFMT 20161128142959 Temp
<213 UTIME OK


When running script again: Log:
/Temp/TempBig.DAT
>PASV
<227 Entering Passive Mode (69,90,66,200,221,162)
>RETR TempBig.DAT
<150-Accepted data connection
<150 1905.0 kbytes to download
<226-File successfully transferred
<226 1.578 seconds (measured here), 1.18 Mbytes per second
>PASV
<227 Entering Passive Mode (69,90,66,200,205,12)
>RETR TempBig.DAT
<150-Accepted data connection
<150 1905.0 kbytes to download
<226-File successfully transferred
<226 1.322 seconds (measured here), 1.41 Mbytes per second
/Temp/TempBig.DAT
>PASV
<227 Entering Passive Mode (69,90,66,200,161,16)
>STOR TempBig.DAT
<150 Accepted data connection
>MFMT 20161116103457 TempBig.DAT
<500 Unknown command
>PASV
<500 Unknown command
>PASV
<500 Unknown command
>PASV
<500 Unknown command
>PASV
<500 Unknown command
>PASV
<500 Unknown command

[RiseFly]

May be BestSync is not very compatible with your FTP server, if you can give us a test account (send email to risefly@risefly.com), we'd like to debug BestSync with your FTP server.