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I have a Raspberry Pi running Raspbian, with Apache2 for the web server. Some recent change seems to have broken my ability to access my web server, when ufw is running. The server simply doesn't respond, rather than rejecting the connection, with the browser giving "myserver took took long to respond". I am able to connect via ssh when this issue is happening.

Looking at the configurations I am at a loss to what could be causing my issue and running with the firewall off is not really a wise option.

The sudo ufw status verbose command gives me (IPv6 address masked) :

Logging: on (low)
Default: deny (incoming), allow (outgoing)
New profiles: skip

To                         Action      From
--                         ------      ----
22                         ALLOW       Anywhere
Anywhere                   ALLOW       192.168.0.0/24
80                         ALLOW       Anywhere
Anywhere                   ALLOW       192.168.2.0/24
443                        ALLOW       Anywhere
22                         ALLOW       Anywhere (v6)
80                         ALLOW       Anywhere (v6)
Anywhere (v6)              ALLOW       fe80::/1
Anywhere (v6)              ALLOW       2001:xxxx:xxxx:xxxx::/64
443                        ALLOW       Anywhere (v6)

Trying sudo iptables --list gives me:

Chain INPUT (policy DROP)
target     prot opt source               destination         
ufw-before-logging-input  all  --  anywhere             anywhere            
ufw-before-input  all  --  anywhere             anywhere            
ufw-after-input  all  --  anywhere             anywhere            
ufw-after-logging-input  all  --  anywhere             anywhere            
ufw-reject-input  all  --  anywhere             anywhere            
ufw-track-input  all  --  anywhere             anywhere            

Chain FORWARD (policy DROP)
target     prot opt source               destination         
ufw-before-logging-forward  all  --  anywhere             anywhere            
ufw-before-forward  all  --  anywhere             anywhere            
ufw-after-forward  all  --  anywhere             anywhere            
ufw-after-logging-forward  all  --  anywhere             anywhere            
ufw-reject-forward  all  --  anywhere             anywhere            

Chain OUTPUT (policy ACCEPT)
target     prot opt source               destination         
ufw-before-logging-output  all  --  anywhere             anywhere            
ufw-before-output  all  --  anywhere             anywhere            
ufw-after-output  all  --  anywhere             anywhere            
ufw-after-logging-output  all  --  anywhere             anywhere            
ufw-reject-output  all  --  anywhere             anywhere            
ufw-track-output  all  --  anywhere             anywhere            

Chain ufw-after-forward (1 references)
target     prot opt source               destination         

Chain ufw-after-input (1 references)
target     prot opt source               destination         
ufw-skip-to-policy-input  udp  --  anywhere             anywhere             udp dpt:netbios-ns
ufw-skip-to-policy-input  udp  --  anywhere             anywhere             udp dpt:netbios-dgm
ufw-skip-to-policy-input  tcp  --  anywhere             anywhere             tcp dpt:netbios-ssn
ufw-skip-to-policy-input  tcp  --  anywhere             anywhere             tcp dpt:microsoft-ds
ufw-skip-to-policy-input  udp  --  anywhere             anywhere             udp dpt:bootps
ufw-skip-to-policy-input  udp  --  anywhere             anywhere             udp dpt:bootpc
ufw-skip-to-policy-input  all  --  anywhere             anywhere             ADDRTYPE match dst-type BROADCAST

Chain ufw-after-logging-forward (1 references)
target     prot opt source               destination         
LOG        all  --  anywhere             anywhere             limit: avg 3/min burst 10 LOG level warning prefix "[UFW BLOCK] "

Chain ufw-after-logging-input (1 references)
target     prot opt source               destination         
LOG        all  --  anywhere             anywhere             limit: avg 3/min burst 10 LOG level warning prefix "[UFW BLOCK] "

Chain ufw-after-logging-output (1 references)
target     prot opt source               destination         

Chain ufw-after-output (1 references)
target     prot opt source               destination         

Chain ufw-before-forward (1 references)
target     prot opt source               destination         
ufw-user-forward  all  --  anywhere             anywhere            

Chain ufw-before-input (1 references)
target     prot opt source               destination         
ACCEPT     all  --  anywhere             anywhere            
ACCEPT     all  --  anywhere             anywhere             state RELATED,ESTABLISHED
ufw-logging-deny  all  --  anywhere             anywhere             state INVALID
DROP       all  --  anywhere             anywhere             state INVALID
ACCEPT     icmp --  anywhere             anywhere             icmp destination-unreachable
ACCEPT     icmp --  anywhere             anywhere             icmp source-quench
ACCEPT     icmp --  anywhere             anywhere             icmp time-exceeded
ACCEPT     icmp --  anywhere             anywhere             icmp parameter-problem
ACCEPT     icmp --  anywhere             anywhere             icmp echo-request
ACCEPT     udp  --  anywhere             anywhere             udp spt:bootps dpt:bootpc
ufw-not-local  all  --  anywhere             anywhere            
 ACCEPT     udp  --  anywhere             224.0.0.251          udp dpt:mdns
ACCEPT     udp  --  anywhere             239.255.255.250      udp dpt:1900
ufw-user-input  all  --  anywhere             anywhere            

Chain ufw-before-logging-forward (1 references)
target     prot opt source               destination         

Chain ufw-before-logging-input (1 references)
target     prot opt source               destination         

Chain ufw-before-logging-output (1 references)
target     prot opt source               destination         

Chain ufw-before-output (1 references)
target     prot opt source               destination         
ACCEPT     all  --  anywhere             anywhere            
ACCEPT     all  --  anywhere             anywhere             state RELATED,ESTABLISHED
ufw-user-output  all  --  anywhere             anywhere            

Chain ufw-logging-allow (0 references)
target     prot opt source               destination         
LOG        all  --  anywhere             anywhere             limit: avg 3/min burst 10 LOG level warning prefix "[UFW ALLOW] "

Chain ufw-logging-deny (2 references)
target     prot opt source               destination         
RETURN     all  --  anywhere             anywhere             state INVALID limit: avg 3/min burst 10
LOG        all  --  anywhere             anywhere             limit: avg 3/min burst 10 LOG level warning prefix "[UFW BLOCK] "

Chain ufw-not-local (1 references)
target     prot opt source               destination         
RETURN     all  --  anywhere             anywhere             ADDRTYPE match dst-type LOCAL
RETURN     all  --  anywhere             anywhere             ADDRTYPE match dst-type MULTICAST
RETURN     all  --  anywhere             anywhere             ADDRTYPE match dst-type BROADCAST
ufw-logging-deny  all  --  anywhere             anywhere             limit: avg 3/min burst 10
DROP       all  --  anywhere             anywhere            

Chain ufw-reject-forward (1 references)
target     prot opt source               destination         

Chain ufw-reject-input (1 references)
target     prot opt source               destination         

Chain ufw-reject-output (1 references)
target     prot opt source               destination         

Chain ufw-skip-to-policy-forward (0 references)
target     prot opt source               destination         
DROP       all  --  anywhere             anywhere            

Chain ufw-skip-to-policy-input (7 references)
target     prot opt source               destination         
DROP       all  --  anywhere             anywhere            

Chain ufw-skip-to-policy-output (0 references)
target     prot opt source               destination         
ACCEPT     all  --  anywhere             anywhere            

Chain ufw-track-input (1 references)
target     prot opt source               destination         

Chain ufw-track-output (1 references)
target     prot opt source               destination         
ACCEPT     tcp  --  anywhere             anywhere             state NEW
ACCEPT     udp  --  anywhere             anywhere             state NEW

Chain ufw-user-forward (1 references)
target     prot opt source               destination         

Chain ufw-user-input (1 references)
target     prot opt source               destination         
ACCEPT     tcp  --  anywhere             anywhere             tcp dpt:ssh
ACCEPT     udp  --  anywhere             anywhere             udp dpt:ssh
ACCEPT     all  --  192.168.0.0/24       anywhere            
ACCEPT     tcp  --  anywhere             anywhere             tcp dpt:http
ACCEPT     udp  --  anywhere             anywhere             udp dpt:http
ACCEPT     all  --  192.168.2.0/24       anywhere            
ACCEPT     tcp  --  anywhere             anywhere             tcp dpt:https
ACCEPT     udp  --  anywhere             anywhere             udp dpt:https

Chain ufw-user-limit (0 references)
target     prot opt source               destination         
LOG        all  --  anywhere             anywhere             limit: avg 3/min burst 5 LOG level warning prefix "[UFW LIMIT BLOCK] "
REJECT     all  --  anywhere             anywhere             reject-with icmp-port-unreachable

Chain ufw-user-limit-accept (0 references)
target     prot opt source               destination         
ACCEPT     all  --  anywhere             anywhere            

Chain ufw-user-logging-forward (0 references)
target     prot opt source               destination         

Chain ufw-user-logging-input (0 references)
target     prot opt source               destination         

Chain ufw-user-logging-output (0 references)
target     prot opt source               destination         

Chain ufw-user-output (1 references)
target     prot opt source               destination  

Have now enabled logging (via sudo ufw logging on) and I see this in the log, corresponding to when the connection attempt is made:

Apr 21 13:29:55 moribito kernel: [ 9889.026870] [UFW BLOCK] IN=eth0 OUT= MAC=b8:27:eb:79:7f:01:68:15:90:41:d7:d8:08:00:45:00:00:40:59:61:40:00:37:06:17:5a SRC=66.131.205.167 DST=192.168.2.42 LEN=64 TOS=0x00 PREC=0x00 TTL=55 ID=22881 DF PROTO=TCP SPT=52048 DPT=11080 WINDOW=65535 RES=0x00 SYN URGP=0 

Additional testing shows the issue only impacts connections coming from outside of the server's local network.

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