Unable top open TCP connection

Pvodoz · 04-17-2018, 08:41 AM

Hi all,
I use a RHEL7.3 server where I have configured a vsftpd server.
I have a weird problem with it.
From a specific remote client, I can only connect to the FTP server one minute on two.
By using tcpdump, I can see that when the connection cannot establish, the server receive the TCP SYN packet from the client but doesn't answer so the client have a timout connection error message...
Do you have any idea of this reason?
I tried watch on iptable, tcpwrapper, etc but didn't find anything!
Thanks for your reply.

JJJCR · 04-19-2018, 03:51 AM

Do you have an active subscription with RHEL?

If you have create a case or search their documentation you might find an idea.

if you ping continuously to port 21 does it timeout?

Have you tried canyouseeme.org and check ftp port status?