Since the latest yum update (the first for a few months) POP3 has stopped working.
I have double checked that pop3 is listed on the public zone and sure enough it is:
firewall-cmd --list-all --zone=public
public (active)
target: default
icmp-block-inversion: no
interfaces: eth0
sources:
services: cockpit dhcpv6-client http https imap imaps pop3 smtp-submission smtps ssh
ports: 25/tcp 80/tcp
protocols:
masquerade: no
forward-ports:
source-ports:
icmp-blocks:
rich rules:
But netstat does not show port 110 to be open:
netstat -tulnp
Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address Foreign Address State PID/Program name
tcp 0 0 0.0.0.0:587 0.0.0.0:* LISTEN 2683/master
tcp 0 0 127.0.0.1:783 0.0.0.0:* LISTEN 863/perl
tcp 0 0 0.0.0.0:465 0.0.0.0:* LISTEN 2683/master
tcp 0 0 0.0.0.0:22 0.0.0.0:* LISTEN 1355/sshd
tcp 0 0 0.0.0.0:25 0.0.0.0:* LISTEN 2683/master
tcp 0 0 0.0.0.0:5666 0.0.0.0:* LISTEN 862/nrpe
tcp 0 0 127.0.0.1:10024 0.0.0.0:* LISTEN 2703/amavisd (maste
tcp 0 0 127.0.0.1:10025 0.0.0.0:* LISTEN 2683/master
tcp 0 0 127.0.0.1:10026 0.0.0.0:* LISTEN 2703/amavisd (maste
tcp6 0 0 :::587 :::* LISTEN 2683/master
tcp6 0 0 ::1:783 :::* LISTEN 863/perl
tcp6 0 0 :::80 :::* LISTEN 860/httpd
tcp6 0 0 :::465 :::* LISTEN 2683/master
tcp6 0 0 :::22 :::* LISTEN 1355/sshd
tcp6 0 0 :::25 :::* LISTEN 2683/master
tcp6 0 0 :::443 :::* LISTEN 860/httpd
tcp6 0 0 :::5666 :::* LISTEN 862/nrpe
tcp6 0 0 ::1:10024 :::* LISTEN 2703/amavisd (maste
tcp6 0 0 ::1:10026 :::* LISTEN 2703/amavisd (maste
udp 0 0 127.0.0.1:323 0.0.0.0:* 659/chronyd
udp6 0 0 ::1:323 :::* 659/chronyd
I have double checked the service file for POP3 exists and includes port 110 and it does.
If I listen on port 110 and ping, this shows up (but the port is reported as closed):
tcpdump -i any port 110
tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
listening on any, link-type LINUX_SLL (Linux cooked), capture size 262144 bytes
12:48:49.060706 IP 198.199.98.246.43347 > domain.net.pop3: Flags [S], seq 3072871086, win 14600, options [mss 1460,sackOK,TS val 3789040058 ecr 0,nop,wscale 8], length 0
12:48:49.060779 IP domain.net.pop3 > 198.199.98.246.43347: Flags [R.], seq 0, ack 3072871087, win 0, length 0
12:48:49.193808 IP 198.199.98.246.43350 > domain.net.pop3: Flags [S], seq 4058864357, win 14600, options [mss 1460,sackOK,TS val 3789040092 ecr 0,nop,wscale 8], length 0
12:48:49.193880 IP domain.net.pop3 > 198.199.98.246.43350: Flags [R.], seq 0, ack 4058864358, win 0, length 0
12:48:49.327749 IP 198.199.98.246.43351 > domain.net.pop3: Flags [S], seq 1901081854, win 14600, options [mss 1460,sackOK,TS val 3789040125 ecr 0,nop,wscale 8], length 0
12:48:49.327824 IP domain.net.pop3 > 198.199.98.246.43351: Flags [R.], seq 0, ack 1901081855, win 0, length 0
If I check mail there is a similar dump but nothing in logged by Dovecot.
