Setting Up Fail2Ban
Abrar Hossain asked: I am new to fail2ban. I want to setup Fail2Ban such that it bans an IP for one hour on two failed login attempts. I have the …
Ipset with Iptables with large list of IP ranges (CIDR)
CvRChameleon asked: I have read some answers here about blocking IP address ranges, and have already used iptables for this purpose before. It is suggested to use ipset in combination …
nftables mangling without NOTRACK: what can happen?
Einheri asked: I’m experimenting with stateless NAT using nftables. On the page about statelessly mangling protocol fields, the author says: Keep in mind the interactions with conntrack, flows with mangled …
IPTables causes conflict with Fail2Ban
IRGeekSauce asked: OS: Ubuntu Server 18.04 Fail2ban: v0.10.2 I am trying to understand a bug with my Fail2ban installation (I believe from my own making). I have a cron job …
Why is this IP6tables configuration blocking IPv6 traffic?
Houman asked: I’m not experienced with IPv6 and am running into a strange situation where I can’t get the current IPv6 by running this curl command: curl -6 ifconfig.io It’s …
Limit IP connection for specific port in forward traffic
Amin asked: I have a server on which I have done port forwarding. This means that each user connects to the server with a dedicated port and the traffic sent …
duplicate packet to another local host(SIEM)
Swannie asked: We have a Central Syslog server that we use to collect all logs from our hosts and recently got a SIEM that we also want to collect the …
Why cannot I access my website when port 80 is not blocked?
William asked: On my VPS(CentOS 7), the default iptables is: Chain INPUT (policy ACCEPT) target prot opt source destination ACCEPT all — 0.0.0.0/0 0.0.0.0/0 state RELATED,ESTABLISHED ACCEPT icmp — 0.0.0.0/0 …
IPTables source NAT (SNAT) to /etc/ufw/before.rules
Tim asked: I have a need to source NAT (SNAT) traffic between two interfaces in an Ubuntu 18.04 server. I’ve been trying to use the ‘/etc/ufw/before.rules’ file to implement my …
Ubuntu 18.04: Communication to server on localhost stops working after setting a port forwarding rule
muliku asked: I have a Ubuntu 18.04 device with two network interfaces, ethernet and USB LTE modem. There is IP camera connected directly to the ethernet port and it has …