[FTPSERVER-481] Artificially running out of passive ports under load

• Type: Bug
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Affects Version/s: 1.1.0
• Component/s: Core
• Environment: Windows 2008R2 virtual machine with 4GB RAM, 4 CPU cores. Oracle Java 1.8.0_121. FTP server configured for 200 users and passive mode ports specified between 3000-3600.
• Assignee: Unassigned
• Reporter: David Brooker
• Created: 06/Mar/17 17:03
• Updated: 11/Apr/17 00:13

Description

When loading the FTP server with 200 users that are downloading files via FTPS in passive mode (implicit), the server eventually appears to run out of passive ports. FTPD log shows numerous instances of "cannot find an available passive port" (see txt attachment). While embedded, it appears the ftpd server also has a memory leak (separate heap dump available upon request - file is too large to attach)

Can be reproduced using JMeter with the attached testplan/ftps plugin in roughly 35 minutes.

Issue Links

• is related to: FTPSERVER-424 Leak of allowed passive ports