See what iptable rule is blocking caddy

After an “apt-get upgrade” my iptables is dropping/blocking requests to my caddy server. I’m using iptables with ufw. The ports are opened through UFW and I can’t find anything causing it. I haven’t added any rules myself after all was running fine which was a couple of months already. See below for iptable rules and the log entyr dropping the request.

Here’s a list of all iptable rules:

-P INPUT DROP
-P FORWARD DROP
-P OUTPUT ACCEPT
-N DOCKER
-N DOCKER-ISOLATION
-N LOGGING
-N ufw-after-forward
-N ufw-after-input
-N ufw-after-logging-forward
-N ufw-after-logging-input
-N ufw-after-logging-output
-N ufw-after-output
-N ufw-before-forward
-N ufw-before-input
-N ufw-before-logging-forward
-N ufw-before-logging-input
-N ufw-before-logging-output
-N ufw-before-output
-N ufw-logging-allow
-N ufw-logging-deny
-N ufw-not-local
-N ufw-reject-forward
-N ufw-reject-input
-N ufw-reject-output
-N ufw-skip-to-policy-forward
-N ufw-skip-to-policy-input
-N ufw-skip-to-policy-output
-N ufw-track-forward
-N ufw-track-input
-N ufw-track-output
-N ufw-user-forward
-N ufw-user-input
-N ufw-user-limit
-N ufw-user-limit-accept
-N ufw-user-logging-forward
-N ufw-user-logging-input
-N ufw-user-logging-output
-N ufw-user-output
-A INPUT -j ufw-before-logging-input
-A INPUT -j ufw-before-input
-A INPUT -j ufw-after-input
-A INPUT -j ufw-after-logging-input
-A INPUT -j ufw-reject-input
-A INPUT -j ufw-track-input
-A INPUT -p icmp -j ACCEPT
-A INPUT -i lo -j ACCEPT
-A INPUT -p tcp -m state --state NEW -m tcp --dport 22 -j ACCEPT
-A INPUT -m state --state RELATED,ESTABLISHED -j ACCEPT
-A INPUT -p udp -m udp --dport 53 -j ACCEPT
-A INPUT -p udp -m udp --dport 5353 -j ACCEPT
-A INPUT -p tcp -m tcp --dport 80 -j ACCEPT
-A INPUT -p tcp -m tcp --dport 8080 -j ACCEPT
-A INPUT -p tcp -m tcp --dport 443 -j ACCEPT
-A INPUT -j REJECT --reject-with icmp-host-prohibited
-A INPUT -j LOGGING
-A FORWARD -j DOCKER-ISOLATION
-A FORWARD -o docker0 -j DOCKER
-A FORWARD -o docker0 -m conntrack --ctstate RELATED,ESTABLISHED -j ACCEPT
-A FORWARD -i docker0 ! -o docker0 -j ACCEPT
-A FORWARD -i docker0 -o docker0 -j ACCEPT
-A FORWARD -j ufw-before-logging-forward
-A FORWARD -j ufw-before-forward
-A FORWARD -j ufw-after-forward
-A FORWARD -j ufw-after-logging-forward
-A FORWARD -j ufw-reject-forward
-A FORWARD -j ufw-track-forward
-A OUTPUT -j ufw-before-logging-output
-A OUTPUT -j ufw-before-output
-A OUTPUT -j ufw-after-output
-A OUTPUT -j ufw-after-logging-output
-A OUTPUT -j ufw-reject-output
-A OUTPUT -j ufw-track-output
-A DOCKER-ISOLATION -j RETURN
-A LOGGING -m limit --limit 2/min -j LOG --log-prefix "IPTables-Dropped: "
-A LOGGING -j DROP
-A ufw-after-input -p udp -m udp --dport 137 -j ufw-skip-to-policy-input
-A ufw-after-input -p udp -m udp --dport 138 -j ufw-skip-to-policy-input
-A ufw-after-input -p tcp -m tcp --dport 139 -j ufw-skip-to-policy-input
-A ufw-after-input -p tcp -m tcp --dport 445 -j ufw-skip-to-policy-input
-A ufw-after-input -p udp -m udp --dport 67 -j ufw-skip-to-policy-input
-A ufw-after-input -p udp -m udp --dport 68 -j ufw-skip-to-policy-input
-A ufw-after-input -m addrtype --dst-type BROADCAST -j ufw-skip-to-policy-input
-A ufw-after-logging-forward -m limit --limit 3/min --limit-burst 10 -j LOG --log-prefix "[UFW BLOCK] "
-A ufw-after-logging-input -m limit --limit 3/min --limit-burst 10 -j LOG --log-prefix "[UFW BLOCK] "
-A ufw-before-forward -m conntrack --ctstate RELATED,ESTABLISHED -j ACCEPT
-A ufw-before-forward -p icmp -m icmp --icmp-type 3 -j ACCEPT
-A ufw-before-forward -p icmp -m icmp --icmp-type 4 -j ACCEPT
-A ufw-before-forward -p icmp -m icmp --icmp-type 11 -j ACCEPT
-A ufw-before-forward -p icmp -m icmp --icmp-type 12 -j ACCEPT
-A ufw-before-forward -p icmp -m icmp --icmp-type 8 -j ACCEPT
-A ufw-before-forward -j ufw-user-forward
-A ufw-before-input -i lo -j ACCEPT
-A ufw-before-input -m conntrack --ctstate RELATED,ESTABLISHED -j ACCEPT
-A ufw-before-input -m conntrack --ctstate INVALID -j ufw-logging-deny
-A ufw-before-input -m conntrack --ctstate INVALID -j DROP
-A ufw-before-input -p icmp -m icmp --icmp-type 3 -j ACCEPT
-A ufw-before-input -p icmp -m icmp --icmp-type 4 -j ACCEPT
-A ufw-before-input -p icmp -m icmp --icmp-type 11 -j ACCEPT
-A ufw-before-input -p icmp -m icmp --icmp-type 12 -j ACCEPT
-A ufw-before-input -p icmp -m icmp --icmp-type 8 -j ACCEPT
-A ufw-before-input -p udp -m udp --sport 67 --dport 68 -j ACCEPT
-A ufw-before-input -j ufw-not-local
-A ufw-before-input -d 224.0.0.251/32 -p udp -m udp --dport 5353 -j ACCEPT
-A ufw-before-input -d 239.255.255.250/32 -p udp -m udp --dport 1900 -j ACCEPT
-A ufw-before-input -j ufw-user-input
-A ufw-before-output -o lo -j ACCEPT
-A ufw-before-output -m conntrack --ctstate RELATED,ESTABLISHED -j ACCEPT
-A ufw-before-output -j ufw-user-output
-A ufw-logging-allow -m limit --limit 3/min --limit-burst 10 -j LOG --log-prefix "[UFW ALLOW] "
-A ufw-logging-deny -m conntrack --ctstate INVALID -m limit --limit 3/min --limit-burst 10 -j RETURN
-A ufw-logging-deny -m limit --limit 3/min --limit-burst 10 -j LOG --log-prefix "[UFW BLOCK] "
-A ufw-not-local -m addrtype --dst-type LOCAL -j RETURN
-A ufw-not-local -m addrtype --dst-type MULTICAST -j RETURN
-A ufw-not-local -m addrtype --dst-type BROADCAST -j RETURN
-A ufw-not-local -m limit --limit 3/min --limit-burst 10 -j ufw-logging-deny
-A ufw-not-local -j DROP
-A ufw-skip-to-policy-forward -j DROP
-A ufw-skip-to-policy-input -j DROP
-A ufw-skip-to-policy-output -j ACCEPT
-A ufw-track-output -p tcp -m conntrack --ctstate NEW -j ACCEPT
-A ufw-track-output -p udp -m conntrack --ctstate NEW -j ACCEPT
-A ufw-user-input -p tcp -m tcp --dport 22 -j ACCEPT
-A ufw-user-input -p udp -m udp --dport 22 -j ACCEPT
-A ufw-user-input -p tcp -m tcp --dport 80 -j ACCEPT
-A ufw-user-input -p udp -m udp --dport 80 -j ACCEPT
-A ufw-user-input -p tcp -m tcp --dport 443 -j ACCEPT
-A ufw-user-input -p udp -m udp --dport 443 -j ACCEPT
-A ufw-user-input -p tcp -m tcp --dport 8888 -j DROP
-A ufw-user-input -p udp -m udp --dport 8888 -j DROP
-A ufw-user-input -p tcp -m tcp --dport 9981 -j ACCEPT
-A ufw-user-input -p udp -m udp --dport 9981 -j ACCEPT
-A ufw-user-input -p tcp -m tcp --dport 9982 -j ACCEPT
-A ufw-user-input -p udp -m udp --dport 9982 -j ACCEPT
-A ufw-user-input -p tcp -m tcp --dport 9091 -j ACCEPT
-A ufw-user-input -p udp -m udp --dport 9091 -j ACCEPT
-A ufw-user-input -p tcp -m tcp --dport 51413 -j ACCEPT
-A ufw-user-input -p udp -m udp --dport 51413 -j ACCEPT
-A ufw-user-input -p tcp -m tcp --dport 6789 -j ACCEPT
-A ufw-user-input -p udp -m udp --dport 6789 -j ACCEPT
-A ufw-user-input -p tcp -m tcp --dport 8881 -j ACCEPT
-A ufw-user-input -p udp -m udp --dport 8881 -j ACCEPT
-A ufw-user-input -p tcp -m tcp --dport 5050 -j ACCEPT
-A ufw-user-input -p udp -m udp --dport 5050 -j ACCEPT
-A ufw-user-input -p tcp -m tcp --dport 6791 -j ACCEPT
-A ufw-user-input -p udp -m udp --dport 6791 -j ACCEPT
-A ufw-user-input -p tcp -m tcp --dport 8989 -j ACCEPT
-A ufw-user-input -p udp -m udp --dport 8989 -j ACCEPT
-A ufw-user-input -p tcp -m tcp --dport 9898 -j ACCEPT
-A ufw-user-input -p udp -m udp --dport 9898 -j ACCEPT
-A ufw-user-input -p tcp -m tcp --dport 8080 -j ACCEPT
-A ufw-user-input -p udp -m udp --dport 8080 -j ACCEPT
-A ufw-user-limit -m limit --limit 3/min -j LOG --log-prefix "[UFW LIMIT BLOCK] "
-A ufw-user-limit -j REJECT --reject-with icmp-port-unreachable
-A ufw-user-limit-accept -j ACCEPT

Here’s the log entry when a request is dropped:

Nov  9 14:26:45 nuc-server kernel: [   88.890482] [UFW BLOCK] IN=eno1 OUT= MAC=ec:a8:6b:fd:7c:69:c8:0e:14:0c:e8:ea:08:00 SRC=62.251.8.80 DST=192.168.178.29 LEN=64 TOS=0x00 PREC=0x00 TTL=62 ID=22080 DF PROTO=TCP SPT=62364 DPT=8080 WINDOW=65535 RES=0x00 SYN URGP=0 

Any help is much appreciated!

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