Bug#977349: Current package does not ensure a smooth upgrade from stable due to breakage of past config and new binary modules.

[Francesco Paolo Lovergine]

Source: proftpd-dfsg
Version: 1.3.7a+dfsg-2
Severity: serious

After upgrade:

$ sudo proftpd -t
Checking syntax of configuration file
2020-12-14 09:59:09,942 legolas proftpd[5444]: mod_dso/0.5: unable to load 'mod_tls.c'; check to see if '/usr/lib/proftpd/mod_tls.la' exists
2020-12-14 09:59:09,942 legolas proftpd[5444]: fatal: LoadModule: error loading module 'mod_tls.c': No such file or directory on line 22 of '/etc/proftpd/modules.conf'
2020-12-14 09:59:09,942 legolas proftpd[5444]: warning: unable to include '/etc/proftpd/modules.conf': Operation not permitted
2020-12-14 09:59:09,943 legolas proftpd[5444]: mod_dso/0.5: unable to load 'mod_wrap.c'; check to see if '/usr/lib/proftpd/mod_wrap.la' exists
2020-12-14 09:59:09,943 legolas proftpd[5444]: fatal: LoadModule: error loading module 'mod_wrap.c': No such file or directory on line 8 of '/etc/proftpd/proftpd.conf'

That's due to mod_wrap and mod_tls move to distinct binaries in the new
version of the package. A transitional package is required, the same problem
is expected in dist-upgrade from stable.

-- System Information:
Debian Release: 10.7
  APT prefers stable-updates
  APT policy: (500, 'stable-updates'), (500, 'stable')
Architecture: amd64 (x86_64)
Foreign Architectures: i386

Kernel: Linux 4.19.0-12-amd64 (SMP w/32 CPU cores)
Kernel taint flags: TAINT_PROPRIETARY_MODULE, TAINT_OOT_MODULE, TAINT_UNSIGNED_MODULE
Locale: LANG=it_IT.UTF-8, LC_CTYPE=it_IT.UTF-8 (charmap=UTF-8), LANGUAGE=it_IT.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /usr/bin/dash
Init: systemd (via /run/systemd/system)
LSM: AppArmor: enabled