Hi,
The problem is not solved even after increasing the delay between each LIST command to 1 minute. Below is the scenario how we call the LIST method.
In out code, we log-in and connect to the ftp server from two different threads.
1st thread opens the connection, issues CWD and closes the connection after every 5 minute.
2nd thread after every 1 minute, opens the connection, issues issues dirdetails() method and closes the connection using quit() method.
After around 23 hours, It is observed that 1st thread is working properly but in case of 2nd thread the control does not come back to our code.
Also now we don't get any error can't open data connection which was coming earlier (when we used to issue LIST method after every 3 secs. without closing and connecting after it for each iteration).
Below is the trace log.
DEBUG [SSLFTPClient] 20