limit incoming connections with host firewall

limit incoming connections on ssh to no more than 6 attempts/30seconds:

ufw limit in log 22/tcp

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also, in netfiler parlance:


/sbin/iptables -N LOGDROP
/sbin/iptables -A LOGDROP -j LOG
/sbin/iptables -A LOGDROP -j DROP
iptables -I INPUT -p tcp --dport 22 -i eth0 -m state --state NEW -m recent --set
iptables -I INPUT -p tcp --dport 22 -i eth0 -m state --state NEW -m recent  --update --seconds 30 --hitcount 6 -j DROP