Build tested:

23.02.3
develop branch
engine: a90535e1a7ffefa0e5ae808fdd0d38d30cffc017
server: 805750b3a90ed4aecbf475025e63674aaab7f7f7
buildNo: 7829

systemctl restart mcs-primproc

[rocky8:root@rocky8~]# mariadb mytest
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A

Welcome to the MariaDB monitor. Commands end with ; or \g.
Your MariaDB connection id is 22
Server version: 10.6.13-8-MariaDB MariaDB Server

Copyright (c) 2000, 2018, Oracle, MariaDB Corporation Ab and others.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

MariaDB [mytest]> truncate lineitem;
ERROR 1815 (HY000): Internal error: CAL0009: Truncate table failed: MCS-2045: At least one PrimProc closed the connection unexpectedly.

Truncate table after "mcs cluster restart" works fine.

After a discussion with leonid.fedorov we came to a conclusion that the problem is caused by TCP socket in DML/DDLProc that stuck when one of PP in a cluster restarts.
DML/DDLProc both establish a connection with PP. When PP goes away presumably the TCP sockets used by DML/DDLProc stick for some time around(they should go down though). There are two approaches to resolve the root cause:

• investigate why the socket to PP doesn't go away and which state it is in TIME-WAIT or something else. We might add a socket state machine event listener.
• if the socket waits for the remote to be closed there should be a way to notify all remote services that PP has been restarted. Controllernode is a good candidate to distribute this event. The other way to reliably distribute the info is via dKVS.