I do not use ftp much lately, but my bro did and noticed we cannot ftp to the server since the upgrade.
Using VSFTP. Tried rebooting but nothing.
Looks like it goes through the whole process and then 'bam'. Could not find an error log that listed the error anywhere.
Worked great before 5.4 update, now it does not work at all.
If you are using iptables, make sure you have ip_conntrack_ftp loaded. This can be accomplished by making sure that ip_conntrack_ftp appears in the "IPTABLES_MODULES" line in /etc/sysconfig/iptables-config and restart iptables. Either that or try turning off iptables temporarily to test.