Debian 11+ProFTPd startup error: proftpd.service: Can't open PID file /run/proftpd.pid - Not connecting from net. about proftpd

[Sgregory54]

Solved - I unknowingly had nftables also running.

[Castaglia]

Hmm. This does not, at first glance, look to be a code issue. The startup sequence (initd, systemd, whatever) is outside of the scope of this project. @hpreusse does this issue look familiar to you at all?

[Sgregory54]

Well, thank you - I had to Configure SYSTEMD:

created missing /etc/systemd/system/proftpd.service - copied from in /lib/systemd/system/proftpd.service

[Unit]
Description=ProFTPD FTP Server
Wants=network-online.target
After=network-online.target nss-lookup.target local-fs.target remote-fs.target

[Service]
Type=forking
Environment=OPTIONS= CONFIG_FILE=/etc/proftpd/proftpd.conf
EnvironmentFile=-/etc/default/proftpd
ExecStartPre=/usr/sbin/proftpd --configtest -c $CONFIG_FILE
ExecStart=/usr/sbin/proftpd -c $CONFIG_FILE $OPTIONS
ExecReload=/bin/kill -HUP $MAINPID
PIDFile=/run/proftpd.pid

[Install]
WantedBy=multi-user.target

then, systemctl daemon-reload
then reloaded proftpd.service

Observed same error in startup status message
Removed PIDFile=/run/proftpd.pid line in etc/systemd/system/proftpd.service

'Can't open PID file' error now gone.

Tried this as well: (Still can't connect to ProFTPd from net)

[Unit]
Description=ProFTPD FTP Server in standalone/socket mode
OnFailure=proftpd.socket
OnSuccess=proftpd.service

[Service]
Type=oneshot
Environment=CONFIG_FILE=/etc/proftpd/proftpd.conf
EnvironmentFile=-/etc/default/proftpd
ExecStart=/usr/bin/grep -iqE '^[[:space:]]*ServerType[[:space:]]+standalone$' $CONFIG_FILE
RemainAfterExit=yes

[Install]
WantedBy=multi-user.target

[Sgregory54]

Still can't connect to ProFTPd from net - only localhost. Seems like a firewall issue.
Disabled SELINUX
I flushed the Iptables and re-entered UFW entries:
ufw status verbose

Status: active
Logging: on (low)
Default: deny (incoming), allow (outgoing), disabled (routed)
New profiles: skip

To                         Action      From
--                         ------      ----
80/tcp                     ALLOW IN    Anywhere                  
443                        ALLOW IN    Anywhere                  
20/tcp                     ALLOW IN    Anywhere                  
21/tcp                     ALLOW IN    Anywhere                  
40000:50000/tcp            ALLOW IN    Anywhere                  
990/tcp                    ALLOW IN    Anywhere                   # FTPS
80/tcp (v6)                ALLOW IN    Anywhere (v6)             
443 (v6)                   ALLOW IN    Anywhere (v6)             
20/tcp (v6)                ALLOW IN    Anywhere (v6)             
21/tcp (v6)                ALLOW IN    Anywhere (v6)             
40000:50000/tcp (v6)       ALLOW IN    Anywhere (v6)             
990/tcp (v6)               ALLOW IN    Anywhere (v6)              # FTPS

I can tail /var/log/messages and see the incoming requests - so firewall is passing port 21?

[Castaglia]

I'm glad you were able to get things working.

[Sgregory54]

Castaglia, Thanks for your suggestion!

I've now learned to issue: sudo service --status-all to be aware of potentially competing services.