configure proftpd to serve ftp and sftp simultaneously - proftpd

Question

Using Ubuntu 18.04 LTS and ProFTPD 1.3.5e.
I have ProFTPD serving FTP on ports 20, 21 and running just fine.
When I add in /etc/proftpd/conf.d/sftp.conf, FTP quits working. When I delete the sftp.conf and restart proftpd, FTP starts working again. I conclude that there is something wrong with this conf file.
Also, I want sftp to accept just a login id and password for authentication. How do I do that? I have looked at the SFTPAuthMethods directive and it looks like if I leave it out then it will allow all authentication methods and that is okay with me.
Here is the sftp.conf file:
<IfModule mod_sftp.c>
SFTPEngine on
Port 2222
SFTPLog /var/log/proftpd/sftp.log
# Configure both the RSA and DSA host keys, using the same host key
# files that OpenSSH uses.
SFTPHostKey /etc/ssh/ssh_host_rsa_key
SFTPHostKey /etc/ssh/ssh_host_dsa_key
SFTPAuthorizedUserKeys file:/etc/proftpd/authorized_keys/%u
# Enable compression
SFTPCompression delayed
</IfModule>
What should I change to get SFTP running on port 2222 and continue to have FTP running on ports 20 & 21?
Thanks in advance!
Update:
Based on the excellent feedback I have received in the notes, instead of using the sftp.conf file I have above, I added a wrapper and some other configuration parameters and have put that config into the proftpd.conf file. It reads as follows:
<snip>
<IfModule mod_sftp.c>
<VirtualHost 0.0.0.0>
# The SFTP configuration
SFTPEngine on
Port 2222
SFTPLog /var/log/proftpd/sftp.log
Include /etc/proftpd/sql.conf
SFTPAuthMethods password keyboard-interactive hostbased publickey
# Configure both the RSA and DSA host keys, using the same host key
# files that OpenSSH uses.
SFTPHostKey /etc/ssh/ssh_host_rsa_key
SFTPHostKey /etc/ssh/ssh_host_dsa_key
SFTPAuthorizedUserKeys file:/etc/proftpd/authorized_keys/%u
# Enable compression
SFTPCompression delayed
</VirtualHost>
</IfModule>
So now the server is answering on FTP ports normally and on port 2222. When I attempt to connect to port 2222 using WinSCP, it fails authentication. Here is the sftp.log file snipped that is generated each time I try to connect.
2020-04-21 21:03:50,340 mod_sftp/0.9.9[13017]: sent server version 'SSH-2.0-mod_sftp/0.9.9'
2020-04-21 21:03:50,355 mod_sftp/0.9.9[13017]: received client version 'SSH-2.0-WinSCP_release_5.17.3'
2020-04-21 21:03:50,355 mod_sftp/0.9.9[13017]: handling connection from SSH2 client 'WinSCP_release_5.17.3'
2020-04-21 21:03:51,284 mod_sftp/0.9.9[13017]: + Session key exchange: ecdh-sha2-nistp256
2020-04-21 21:03:51,284 mod_sftp/0.9.9[13017]: + Session server hostkey: ssh-rsa
2020-04-21 21:03:51,284 mod_sftp/0.9.9[13017]: + Session client-to-server encryption: aes256-ctr
2020-04-21 21:03:51,284 mod_sftp/0.9.9[13017]: + Session server-to-client encryption: aes256-ctr
2020-04-21 21:03:51,284 mod_sftp/0.9.9[13017]: + Session client-to-server MAC: hmac-sha2-256
2020-04-21 21:03:51,284 mod_sftp/0.9.9[13017]: + Session server-to-client MAC: hmac-sha2-256
2020-04-21 21:03:51,285 mod_sftp/0.9.9[13017]: + Session client-to-server compression: none
2020-04-21 21:03:51,285 mod_sftp/0.9.9[13017]: + Session server-to-client compression: none
2020-04-21 21:03:51,957 mod_sftp/0.9.9[13017]: sending acceptable userauth methods: password,keyboard-interactive,hostbased,publickey
2020-04-21 21:03:52,302 mod_sftp/0.9.9[13017]: expecting USER_AUTH_INFO_RESP message, received SSH_MSG_IGNORE (2)
2020-04-21 21:03:52,322 mod_sftp_pam/0.3[13017]: PAM authentication error (7) for user 'test': Authentication failure
For FTP, I am authenticating successfully from a MySQL database. But the last line of the sftp.log file says that PAM authentication failed for my SFTP attempt. I am just trying to authenticate in the WinSCP client with a login and password that come from MySQL. Does that involve PAM authentication?
I think I am getting close!
Thanks in advance!

Answer 1

Here is the full /etc/proftpd/proftpd.conf that accomplishes my goals as stated above.
Note that I am also using mod_sql to provide for authentication via MySQL. So there are other configuration files referenced by this config file but are not listed in this posting.
# cat /etc/proftpd/proftpd.conf
# /etc/proftpd/proftpd.conf -- This is a basic ProFTPD configuration file.
# To really apply changes, reload proftpd after modifications, if
# it runs in daemon mode. It is not required in inetd/xinetd mode.
#
# Includes DSO modules
Include /etc/proftpd/modules.conf
# Set off to disable IPv6 support which is annoying on IPv4 only boxes.
UseIPv6 on
# If set on you can experience a longer connection delay in many cases.
IdentLookups off
ServerName "hostname"
# Set to inetd only if you would run proftpd by inetd/xinetd.
# Read README.Debian for more information on proper configuration.
ServerType standalone
DeferWelcome off
MultilineRFC2228 on
DefaultServer on
ShowSymlinks on
TimeoutNoTransfer 600
TimeoutStalled 600
TimeoutIdle 1200
DisplayLogin welcome.msg
DisplayChdir .message true
ListOptions "-l"
DenyFilter \*.*/
# Use this to jail all users in their homes
DefaultRoot ~
# This line will create the user directories of an FTP user if they successfully authenticate but do not have a user directory.
# See http://www.proftpd.org/docs/howto/CreateHome.html
# CreateHome off|on [<mode>] [skel <path>] [dirmode <mode>] [uid <uid>] [gid <gid>] [homegid <gid>] [NoRootPrivs]
CreateHome on dirmode 750
# Users require a valid shell listed in /etc/shells to login.
# Use this directive to release that constrain.
RequireValidShell off
# Port 21 is the standard FTP port.
Port 21
# In some cases you have to specify passive ports range to by-pass
# firewall limitations. Ephemeral ports can be used for that, but
# feel free to use a more narrow range.
# PassivePorts 49152 65534
# If your host was NATted, this option is useful in order to
# allow passive transfers to work. You have to use your public
# address and opening the passive ports used on your firewall as well.
# MasqueradeAddress 1.2.3.4
# This is useful for masquerading address with dynamic IPs:
# refresh any configured MasqueradeAddress directives every 8 hours
<IfModule mod_dynmasq.c>
# DynMasqRefresh 28800
</IfModule>
# To prevent DoS attacks, set the maximum number of child processes
# to 30. If you need to allow more than 30 concurrent connections
# at once, simply increase this value. Note that this ONLY works
# in standalone mode, in inetd mode you should use an inetd server
# that allows you to limit maximum number of processes per service
# (such as xinetd)
MaxInstances 50
# Set the user and group that the server normally runs at.
User proftpd
Group nogroup
# Umask 022 is a good standard umask to prevent new files and dirs
# (second parm) from being group and world writable.
Umask 022 022
# Normally, we want files to be overwriteable.
AllowOverwrite on
# Uncomment this if you are using NIS or LDAP via NSS to retrieve passwords:
# PersistentPasswd off
# This is required to use both PAM-based authentication and local passwords
# AuthOrder mod_auth_pam.c* mod_auth_unix.c
# Be warned: use of this directive impacts CPU average load!
# Uncomment this if you like to see progress and transfer rate with ftpwho
# in downloads. That is not needed for uploads rates.
#
# UseSendFile off
TransferLog /var/log/proftpd/xferlog
SystemLog /var/log/proftpd/proftpd.log
# Logging onto /var/log/lastlog is enabled but set to off by default
#UseLastlog on
# In order to keep log file dates consistent after chroot, use timezone info
# from /etc/localtime. If this is not set, and proftpd is configured to
# chroot (e.g. DefaultRoot or <Anonymous>), it will use the non-daylight
# savings timezone regardless of whether DST is in effect.
#SetEnv TZ :/etc/localtime
<IfModule mod_quotatab.c>
QuotaEngine off
</IfModule>
<IfModule mod_ratio.c>
Ratios off
</IfModule>
# Delay engine reduces impact of the so-called Timing Attack described in
# http://www.securityfocus.com/bid/11430/discuss
# It is on by default.
<IfModule mod_delay.c>
DelayEngine on
</IfModule>
<IfModule mod_ctrls.c>
ControlsEngine off
ControlsMaxClients 2
ControlsLog /var/log/proftpd/controls.log
ControlsInterval 5
ControlsSocket /var/run/proftpd/proftpd.sock
</IfModule>
<IfModule mod_ctrls_admin.c>
AdminControlsEngine off
</IfModule>
#
# Alternative authentication frameworks
#
#Include /etc/proftpd/ldap.conf
Include /etc/proftpd/sql.conf
#
# This is used for FTPS connections
#
#Include /etc/proftpd/tls.conf
#
# Useful to keep VirtualHost/VirtualRoot directives separated
#
#Include /etc/proftpd/virtuals.conf
# A basic anonymous configuration, no upload directories.
# <Anonymous ~ftp>
# User ftp
# Group nogroup
# # We want clients to be able to login with "anonymous" as well as "ftp"
# UserAlias anonymous ftp
# # Cosmetic changes, all files belongs to ftp user
# DirFakeUser on ftp
# DirFakeGroup on ftp
#
# RequireValidShell off
#
# # Limit the maximum number of anonymous logins
# MaxClients 10
#
# # We want 'welcome.msg' displayed at login, and '.message' displayed
# # in each newly chdired directory.
# DisplayLogin welcome.msg
# DisplayChdir .message
#
# # Limit WRITE everywhere in the anonymous chroot
# <Directory *>
# <Limit WRITE>
# DenyAll
# </Limit>
# </Directory>
#
# # Uncomment this if you're brave.
# # <Directory incoming>
# # # Umask 022 is a good standard umask to prevent new files and dirs
# # # (second parm) from being group and world writable.
# # Umask 022 022
# # <Limit READ WRITE>
# # DenyAll
# # </Limit>
# # <Limit STOR>
# # AllowAll
# # </Limit>
# # </Directory>
#
# </Anonymous>
# Include other custom configuration files
Include /etc/proftpd/conf.d/
<IfModule mod_sftp.c>
<VirtualHost 0.0.0.0>
# The SFTP configuration
SFTPEngine on
Port 2222
SFTPAuthMethods password
RequireValidShell off
SFTPLog /var/log/proftpd/sftp.log
Include /etc/proftpd/sql.conf
# Configure both the RSA and DSA host keys, using the same host key
# files that OpenSSH uses.
SFTPHostKey /etc/ssh/ssh_host_rsa_key
SFTPHostKey /etc/ssh/ssh_host_dsa_key
#SFTPAuthorizedUserKeys file:/etc/proftpd/authorized_keys/%u
# Enable compression
SFTPCompression delayed
DefaultRoot ~
</VirtualHost>
</IfModule>
# Time stamp - IP Address - Protocol - User Name - UID - Filename - File Sizeo - Response Time in Milliseconds - Transfer Time in Seconds - Transfer Status - Reason for failure if applicable
# http://www.proftpd.org/docs/modules/mod_log.html#LogFormat
LogFormat custom "%{iso8601} %a %{protocol} %u %{uid} %f %{file-size} %R %T %{transfer-status} %{transfer-failure}"
ExtendedLog /var/log/proftpd/custom.log READ,WRITE custom

Answer 2

The essence of the solution to make it listen on both FTP 21 and SFTP 2222 is to add <VirtualHost 0.0.0.0> section inside of <IfModule mod_sftp.c>:
...
Port 21
...
<IfModule mod_sftp.c>
<VirtualHost 0.0.0.0> # << *** this part makes it listen on both 21 above and 2222 below ***
...
Port 2222
...
</VirtualHost> # << closing tag
</IfModule>
(thanks to the original question author and his response, eyeballing two configs I was able to boil it down to this)