sync_client stop working suddenly

[Patrice]

Hi,

my sync_client stopped working since yesterday evening.
I have searched around , but no way to make it work again.
I tried to stop/start cyrus-imap but it does not help

my cyrus-imap version is: 2.3.1

when I do a 'ps' I don't see the 2 'sync_client' I used to have.
even when I launch it by hand it does not work:
'sync_client -C /etc/imapd-master.conf -r'

and even with verbose I don't see anything.
ssl certificates are still there and accessible.

on my replica I see this:
Mar 28 18:06:16 replica cyrus/master[6804]: process 6862 exited, 
signaled to death by 7

what could have happened ?
Does someone have an idea ?


Thank you for you help

Patrice