If possible, save the console output. There may be clues to diagnose the problem.
<command> | tee mylog

machine a:

Linux v165062 2.6.32-042stab140.4 #1 SMP Fri Oct 11 11:36:17 MSK 2019 i686 GNU/Linux

sysvinit and related programs: 2.88dsf-59.9+devuan2_i386

machine b:

Linux v165051 2.6.32-042stab140.4 #1 SMP Fri Oct 11 11:36:17 MSK 2019 i686 GNU/Linux

sysvinit and related programs: 2.88dsf-59.2+devuan2_i386
dependencies all on latest patch level like machine a, well except the selinux lib.

You see two vservers in an old OpenVZ environment hosted on the same physical hardware. Both started as Debian 7 installations and were upgraded through Debian/Devuan lenny.

Machine a(!) hangs during init, machine b boots just fine. During the upgrade of machine a, sysvinit-core did not install correctly. I reinstalled manually from the system console.
Strange enough, sysvinit-core was simply not upgraded on machine b - apt's che provides the younger binary, not the installed version.

I found a dirty workaround to get machine a up and running:

/etc/init.d/networking stop
/etc/init.d/networking start
then start the contents of /etc/rc3.d in a for loop.

I am looking for a hint to make machine a a fully bootable again. Downgrade sysvinit-core and all its dependencies? How?
Better suggestions?

BTW: both machines are productive servers, so rebooting is a problem. Especially on machine b.