Upgrade en Plesk Obsidian partiellement banca (no mail/no plesk) l- help urgent!

Bonjour,
[ Plesk Obsidian 18.0.32.2
OS version: CentOS 7 x86_64
Build date: 2020/12/21 13:00]

Après avoir effectué un upgrade de Plesk 17.x à Obsidian 18.0.32.2, le serveur de mail ne fonctionne plus (ni webmail -Roundcube- ni via un client mail) et l’interface de Plesk m’affiche après login une belle **erreur 500 avec un message “Call to undefined function plesk_str_replace()**
File common_func.php
Line 576”

Les sites sont accessibles (Apache,ProFTPD et MySQL tournent), Let’s Encrypt fonctionne (les sites ainsi que Plesk sont en https), d’autres services fonctionnent (fail2ban,AWStats, watchdog, etc…) pourtant un top, montre dovecot/postfix comme étant up).

**Le plus urgent étant de récupérer le service mail.**

Voici le output de mes différents essais de réparation avec Plesk en ligne de commande.

#1
ERROR: No supported protocols supplied.
Run sslmng --help to view help.

Warning: configure SSL ciphers and protocols for:

_(et réponse sslmng : commande introuvable)?!_

et
Bootstrapper repair finished.
Errors occurred while performing the following actions: cumulative Plesk upgrade and repair final stage, restore mail, configure SSL ciphers and protocols, regenerate web servers configuration files, fix Plesk packages permissions.

#2
Reconfiguring mail subsystem...
Trying to execute mail_restore to synchronize mail server settings and Plesk Database... ==> Checking for: mailsrv_conf_init... fail

#3
[2021-01-05 13:12:43.434385] Warning: Failed to attach to cgroup /sys/fs/cgroup/cpu/tasks, installer might be unexpectedly killed later by the system
[2021-01-05 13:12:43.439498] Error: L'utilitaire yum n'a pas réussi à installer les packs requis.
Attention ! Votre logiciel risque de ne pas fonctionner.


Warning: configure SSL ciphers and protocols for:
Warning: reconfigure web-server configurations skipping broken domains
Warning: reconfigure web-server configurations skipping broken domains
STOP Bootstrapper 18.0.32 repair AT Wed Jan 6 21:36:14 CET 2021: PROBLEMS FOUND

#4
ERROR: Error: Class 'Service_Agent_Transport_Util' not found (common_func.php:485)

Warning: reconfigure web-server configurations skipping broken domains

***** problem report *****
Warning: configure SSL ciphers and protocols for:
Warning: reconfigure web-server configurations skipping broken domains
Warning: reconfigure web-server configurations skipping broken domains



**Le Output of /var/log/plesk/install/plesk_18.0.32_repair.log**
(…)
===> Cumulative Plesk upgrade and repair (final stage) has been started.
===> Preparing Plesk upgrade (final stage).
Trying to remove compiled Python modules... done
Trying to transfer panel logs to system logrotate... done
Creating /var/lib/plesk/sslmng.json based on current settings in DB
Traceback (most recent call last):
File "", line 9, in
KeyError: 'ssl-protocols'
Creating /var/lib/plesk/sslmng.json based on current settings in DB
Traceback (most recent call last):
File "", line 9, in
KeyError: 'ssl-protocols'
After end of upgrade for 'core' (stage 'post') following actions are registered as failed: 20200423164000-create_stored_sslmng_configuration 20200423164001-create_stored_sslmng_configuration.
===> Plesk was not upgraded completely. See installation log for details.
Reconfiguring mail subsystem...
Trying to execute mail_restore to synchronize mail server settings and Plesk Database... ==> Checking for: mailsrv_conf_init... fail

(…)
Reconfiguring SSL ciphers and protocols...
Trying to configure SSL ciphers and protocols for: ... PHP Warning: "continue" targeting switch is equivalent to "break". Did you mean to use "continue 2"?; File: /usr/local/psa/admin/plib/Service/Agent/Transport/Util.php, Line: 134

[2021-01-05 17:52:51.112] ERR [panel] Class 'Service_Agent_Transport_Util' not found:


**Le output de plesk_18…… _repair_problems.log**
***** problem report *****
Warning: configure SSL ciphers and protocols for:
Warning: reconfigure web-server configurations skipping broken domains
Warning: reconfigure web-server configurations skipping broken domains
STOP Bootstrapper 18.0.32 repair AT Thu Jan 7 15:24:35 CET 2021: PROBLEMS FOUND


Si quelqu’un peut me sortir de ce mauvais pas!
Il semble que les certificats SSL (Let's encrypt) soient en cause au moins partiellement mais je ne trouve pas de solution.


PS : accessoirement, j’ai une erreur dans /var/log/plesk/install/plesk-whc-installation.log
ln: failed to create hard link '/var/www/vhosts/chroot/etc/resolv.conf' => '/etc/resolv.conf': Invalid cross-device link
done


Merci d'avance au messie ;-)