Postings by Sean Son

Question about disabling SSLv2 and SSLv3 and Opportunistic TLS

Hello all

I have opportunistic TLS (offering STARTLS) configured in my
file. I have been tasked to disable SSLv2 and SSLv3 as well as disable
medium strength ciphers (to use high strength ones instead) in my postfix
server. If I was to add the following to my


will this be enough to disable medium strength ciphers as well as disable
SSLv2/v3? Or will I need more?

Offering STARTTLS in postfix. need help!

hello everyone

I hope you all had a wonderful holiday season.

How does one configure an internet facing Postfix SMTP mail relay server,
to offer STARTTLS? I have been googling around and seeing various
different articles and blog entries, but I cannot figure out what is the
quickest and easiest way to do so. I am running postfix on RHEL 7. Any
help is greatly appreciated!



Struts vulnerability

Hello all

I am new to the mailing list as well as new to Apache Struts. We all heard
in the news about the vulnerability affecting Apache Struts. I have been
tasked to determine which of our servers have Struts running on them.

Monitoring Postfix Mail queue with SNMP

Hello all

We would like to monitor Postfix mail queues using SMNP so we can receive
alerts whenever the mail queue reaches a certain threshold. What OID and
MIB would we have to use to be able to monitor Postfix mail queues?

Thank you for all of your help in this post and other posts of mine!


How do I move messages from a sender to the HOLD queue?

Hello all

We have over a thousand messages from a certain user that are stuck in our
mail queue. Is there a way to move those messages to the HOLD queue for
now? I want to move all messages from that specific sender, to the HOLD

All help is greatly appreciated!



Migrating Postfix mail account to a new mail account without losing mail

Hello all

I have an user who has a number of mail accounts on our Postfix server. He
is interested in knowing if its possible to migrate these accounts to new
accounts with out losing any old mail? For example:

current mail account: <a href="mailto: ... at mymailserver dot com"> ... at mymailserver dot com</a>

new mail account: <a href="mailto: ... at mymailserver dot com"> ... at mymailserver dot com</a>

He wants to migrate all of the data from the current mail account to the
new mail account with out losing any mail. Eventually the current account
will be decommissioned and the new account will be used.

Strange ABRT error when I try to switch to su

Hello all

One of my VMs, running RHEL 7, has been giving me the following ABRT error
when I try to login as su Ive seen this error the past three times that
Ive logged in. I know that the VM is using Red Hat,but seeing that
RHEL/CentOS are pretty much the same thing, I figured I should ask the
CentOS mailing list for help. Here is the error:

$ su
ABRT has detected 1 problem(s).

Using Postfix with a Dual Homed Server

Hello all

We have a recently set up a dual homed VM running Postfix. We set up
policy based routing to allow for each of the two NICs to have a different
IP with different subnets. This server is an SMTP Relay server. Will
postfix work properly with a dual homed VM? Or will the postfix service
only bind to one NIC? In our file , inet_interfaces is set to all.



Need help getting two NICs to work on CentOS 7

Hello all

Here is the scenario: We have a mail server VM which currently has two
virtual NICs attached to it. One NIC is has an IP on a subnet with a
default gateway defined and the other NIC has an IP on a different subnet
with a different gateway on a different VLAN defined. Now when I activate
both NICs, and run an ifconfig -a, I see that both IP addresses are
showing. Now here is the problem. When I ping the VM, the first NIC's IP is
not pingable at all, but the second NIC's IP is pingable.

Cannot figure out what this segfault message means. Please help!

Hello all

I installed MySQL 5.7 using the Mysql community YUM repository and I also
installed Tomcat 8 from The installations went fine but
ive been noticing that the VM,which is running CentOS 7.2, has been
freezing periodically.