Directory listing failed in FileZilla with ProFTPd on Virtualmin

Everything appears normal in the FTP server’s log:
fr01-srv proftpd[5591]: 192.168.0.1 – USER testuser: Login successful.

However, in Filezilla things are different:
Error: Connection timed out after 20 seconds of inactivity Error: Failed to retrieve directory listing

iptables modules for OpenVZ kernel

This is my preferred list of modules for iptables on OpenVZ kernels (set in /etc/vz/vz.conf): ## IPv4 iptables kernel modules to be enabled in CTs by default IPTABLES=”ipt_REJECT ipt_tos ipt_TOS ipt_LOG ip_conntrack ipt_limit ipt_multiport iptable_filter iptable_mangle ipt_TCPMSS ipt_tcpmss ipt_ttl ipt_length ipt_state iptable_nat ip_nat_ftp ipt_owner ipt_REDIRECT” ## IPv4 iptables kernel modules …