Am 10.12.2014 um 22:59 schrieb Julian Mehnle:
I'm running Postfix 2.11.0 on Ubuntu 14.04.1 LTS on multiple m3.xlarge
instances (15GB RAM) on Amazon EC2. There's a milter plugged in. This setup has
been running without problems on Postfix 2.9.6 on Ubuntu 12.04.2 LTS on bare
metal machines (32GB RAM) for years. Only when we ported it to EC2 did we start
seeing the following warnings:
Dec 10 12:47:27 fbr-sample-00 postfix/smtpd[2350]: warning: connect to
private/tlsmgr: Resource temporarily unavailable
Dec 10 12:47:27 fbr-sample-00 postfix/smtpd[2350]: warning: problem talking to
server private/tlsmgr: Resource temporarily unavailable
I did some digging in mailing list archives and on the web, and the most
relevant reference I've been able to find was an old postfix-users thread
saying this could be caused by a shortage of entropy from a blocking entropy
source, such as /dev/random. However, Ubuntu's Postfix is compiled to use
/dev/urandom, which is not supposed to block:
$ postconf tls_random_source
tls_random_source = dev:/dev/urandom
Also, it seems like we have plenty of entropy available:
$ cat /proc/sys/kernel/random/entropy_avail
877
I've never seen it dip below 750
but at the same moment as the warnings appear?
http://linux.die.net/man/8/haveged is mandatory on a virtual server
