Having an issue with ftp put, 'ftp_put' returns false and files are only transferred incompletely. The error returned is 426 Failure reading network stream. Also got 'Transfer aborted' error when tried to upload files to another server.

Restart of the server is fixing the issue for 2 or 3 days. I tried with a third server too, this time it was uploaded to that server. But still issue persists with the other servers.

Any possible chances for resource locks which automatically fixed while restarting the server. What are the main logs to check for this issue? Also where should I check to know if some resource locking happens? Or something else which will be helpful to solve this issue...

Destination server is using vsftpd and the source is having proftpd sever. Is there any changes needed in the configuration source or detination servers? What could be the reason for failure of these file uploads until restart of the source server and 426 network streaming error?

ftp> put testfile.mp3
local: testfile.mp3 remote: testfile.mp3
ftp: setsockopt (ignored): Permission denied
---> PORT x,x,x,x,54,85
200 PORT command successful. Consider using PASV.
---> STOR testfile.mp3
150 Ok to send data.
426 Failure reading network stream.
279040 bytes sent in 0.01 secs (24289.2 kB/s)


Thanks in advance for the help.

Approach it logically. Try some of these.
Have you tried sftp, part of ssh & friends? Does it still crash?
Have you tried a different network interface? Different interrupt on the same interface?
Nothing silly on the disk (e.g. errors) or poorly installed/buggy programs?
Is the server hiding behind NAT which may muck around with port numbers?
Anything in the logs?
Try and eliminate things and verify parts at a time.