On 30/3/2022 4:56 μ.μ., Nikolaos Milas wrote:
In the meantime, I have identified more mails that users considered
delivered successfully, but there is no sign of them in the logs; we
should conclude that these mails were in fact not sent/received at all?
Answering my own question, apparently mail (I cannot determine if ALL of
it) IS in fact getting delivered, even if not logged in all cases.
Answering to Victor, who replied to me in the meantime and provided
valuable hints, esp. about the journal, I found that mail that is NOT
logged in /var/log/maillog IS in fact recorded successfully in the
systemd journal!
I was wondering if low I/O performance of the virtual Hard Disk could
lead to log entries not getting written successfully. This VM features a
large virtual HD (see specs below) that is apparently associated with
low I/O performance.
I'll have to check how to configure postfix service to NOT use the
journal but only the rsyslog facility. Would this probably lead to
having full (i.e. without misses) logging at /var/log/maillog?
For reference:
# cat /etc/redhat-release
CentOS Linux release 7.9.2009 (Core)
# uname -r
3.10.0-1160.59.1.el7.x86_64
# mpstat
Linux 3.10.0-1160.59.1.el7.x86_64 (vmail2.noa.gr) 03/30/2022
_x86_64_ (1 CPU)
05:43:59 PM CPU %usr %nice %sys %iowait %irq %soft %steal
%guest %gnice %idle
05:43:59 PM all 9.02 0.03 4.09 1.47 0.00 0.17 0.33
0.00 0.00 84.90
# free -m
total used free shared buff/cache
available
Mem: 4797 1036 1167 218 2593 3289
Swap: 4991 0 4991
# df -hT
Filesystem Type Size Used Avail Use%
Mounted on
devtmpfs devtmpfs 2.4G 0 2.4G 0% /dev
tmpfs tmpfs 2.4G 0 2.4G 0%
/dev/shm
tmpfs tmpfs 2.4G 219M 2.2G 10% /run
tmpfs tmpfs 2.4G 0 2.4G 0%
/sys/fs/cgroup
/dev/mapper/cl-root xfs 3.0T 1.5T 1.6T 48% /
/dev/vda2 xfs 1014M 311M 704M 31% /boot
10.201.40.34:/data/col1/noc-bkups-1 nfs 19T 9.7T 8.5T 54%
/mnt/dd2500-1
10.201.40.34:/data/col1/noa-mailboxes nfs 19T 9.7T 8.5T 54%
/mnt/mailbox-backups
tmpfs tmpfs 480M 0 480M 0%
/run/user/495
tmpfs tmpfs 480M 0 480M 0%
/run/user/0
# rpm -qa | grep syslog
rsyslog-8.24.0-57.el7_9.1.x86_64
Many thanks,
Nick
