Locally route traffic from DMZ-server to firewall’s public IP address [duplicate]

This question already has answers here: Loopback to forwarded Public IP address from local network – Hairpin NAT (12 answers) Closed 4 years ago. I have an Ubuntu server that sits in a DMZ. The server has a private IP address (10.x.x.x) and the firewall has a public IP address. All network traffic from internet … Read more

I am configuring OpenVPN in Ubuntu but unable to add 1194 port in UFW firewall [closed]

Closed. This question needs details or clarity. It is not currently accepting answers. Want to improve this question? Add details and clarify the problem by editing this post. Closed 6 days ago. Improve this question lo: flags=73<UP,LOOPBACK,RUNNING> mtu 65536 inet netmask inet6 ::1 prefixlen 128 scopeid 0x10<host> loop txqueuelen 1000 (Local Loopback) RX … Read more

Ubuntu Firewall blocking DNS requests to VMWARE guest with outbound traffic rules added and stateful matching done

This is a unique problem related to DNS queries(tcp/udp 53) even with correct UFW/iptables rules and does not relate to /etc/resolv.conf I can ping google DNS but cannot resolve google.com after turning on the host ufw. Tried searching everywhere and updated ufw and iptables accordingly to allow DNS queries and allow established connection. My … Read more

Trouble configuring sendmail to relay mail [duplicate]

This question already has an answer here: SMTP 25 closed even though I allow everything in firewall (Debian server running sendmail) (1 answer) Closed 8 years ago. I am trying to configure sendmail and ufw on an ubuntu server (ServerA) so that another server (ServerB) can send mail through it. In my /etc/mail/access file I … Read more

UFW deny not working

The basic configuration is the following: To Action From — —— —- Anywhere DENY xx.xxx.xxx 22/tcp ALLOW Anywhere 80/tcp ALLOW Anywhere 22/tcp (v6) ALLOW Anywhere (v6) 80/tcp (v6) ALLOW Anywhere (v6) Not using ipv6, verivied ipv4. varnish and nginx logs show the ipv4 address that should be nuked from space. ubuntu 16.04, ufw 0.35 iptables … Read more