Mails suddenly stuck on ESA
for any reason since yesterday my ESA (10.0.6) stopped delivering mails properly, outbound mails got stuck in the queue with the following reason, e.g.
Timed out, status = ETIMEDOUT while connecting from dispatch.bwc.de (0.0.0.0) to smtp.customer.com (188.8.131.52)
On the firewall I can see that the ESA is reaching the destination server on the internet, it's no connectivity issue though. Sometimes the mails are going through after a while, but mostly they are stuck. Sometimes a manual force delivery succedes but not always. All kinds of remote servers are affected, no pattern visible.
No changes were made on my end and I'am somewhat confused.