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Postings by JDN

smtp relay server security

Hello

How can we secure are postfix smtp relay server?

For the moment we have a rule that only allow mail from exchange server adres to postfix (relay server), but when somebody spoofs this address mail gets accept and you can send your mail to anybody as anybody.

When I check:
[administrator@eqx-mailman02 ~]$ sudo postconf -a
[sudo] wachtwoord voor administrator:
cyrus
dovecot

So I know I can use these but we are not used of working with this.

Can we setup another way of authentication?

I would not like to setup users/mailboxes on the relay server, all are users are on the exchange ser

transfer mailq

Hello

We are busy with a POC building a new vessel mail system for are fleet at sea .
In our office we have now to postfix servers running behind a F5 that has failover when primary mail server goes down the second one takes over.

So far so good, we test this and everything is oke.

Now I want to know if it's possible to transfer mail files that are qued on server A to server B to get send when A goes down.

I would like to do this as follows

Create two folders on a nfs share

Server A writes his mails to folder A
Server B writes his mails to folder B

When server A crashes we copy/transfe

postfix as relay server: sasl auth

Hello

We have setup a postfix server that serves as a relay server between the office and our fleet.

The postfix gets his mails from the exchange server onboard.
The restriction is set that only mails from the ip of the exchange are accepted.

And this security rule works, from no other ip mails can be send.

+But are sec officer is worried what is somebody gets in to the vm running the exchange server, or creates a vm that has the same ip as the exchange, than can you send mails without auth.

That's why I'm searching to a way to secure are postfix server with password and username.

I'm

RE: nfs as storage for mail queue

Found a solution to my problem in archive

<a href="http://postfix.1071664.n5.nabble.com/scan-dir-push-open-directory-defer-Permission-denied-td90566.html" title="http://postfix.1071664.n5.nabble.com/scan-dir-push-open-directory-defer-Permission-denied-td90566.html">http://postfix.1071664.n5.nabble.com/scan-dir-push-open-directory-defer-...</a>

thanks Witse

Met vriendelijke groeten
Kind regards
De Petter Mattheas
Technical support engineer - projects team
IT-Department Jan De Nul Dredging N.V.
T +32 (0)53 73 95 53
F +32 (0)53 21 00 31
www.jandenul.com<http://www.jandenul.com/>

Hello

Can somebody help me?

So I have setup the nfs share on a windows se

nfs as storage for mail queue

Hello

Can somebody help me?

So I have setup the nfs share on a windows server 2016 with nfs server role.

Security is set on the device ip of the postfix server read-write with allow root access.

In the main conf of postfix I have set the queue to the right dir

queue_directory = /mnt/mail

fstab is set as:
10.7.248.45:/Mailq /mnt/mail nfs defaults 0 0

When I start the postfix service it writes all the folder structure on the share but fails to start with error.

‚óŹ postfix.service - Postfix Mail Transport Agent
Loaded: loaded (/usr/lib/systemd/system/postfix.service; enabled; vendor pre

nfs as mailq storage?

Hello

Is there a way for postfix to store its mailq on a nfs share?

And what do i need to change to make it store the q over there.

The nfs share is mounted to the postfix server in the fstab config file.

Case for this is, we are using postfix in a poc case for are vessel mail as= a relay host.

So when we have sat communication mail leaves the vessel on the spot, but w= hen we have not sat comm mail has to stay in queue until sat comes back.

Thing is when are vessel is in voyage on the ocean there are places where t= here is no coverage and mails get for long time in queue.

A

stress tested postfix

Hello

We just did a stress test on the posfix server we installed in are test lab= , specs: 4 virtual cpu and 4GB ram on a vmware esx environment.

Test os ubuntu 18.04.2 fully patched

Kernel 4.15.0.46

Postfix version is the one from ubuntu repo 3.3

We see when we send 45000 mails form are exchange server to the relay smtp =

(postfix) that postfix loses about 14000 mails.

About 31000 are in are postfix que and the rest is gone, on are exchange we= see the confirmation of postfix that he has received the mail is not in th= e postfix que.

We see a very high I/O on the disk but stil

best practice for HA cluster

Hello

Which work method do you guys prefer for ha with postfix?

2 postfix nodes with f5 load balancer active passive and shared storage for the que
How can you share config between active and passive ?

Mysql and postfix mail que

hello you all

Can I set a mysql database for the mails that our in the mail que to get
send? and map that database to two postfix servers that our behind a F5 load
balancer set active passive?

so if active goes down the second one still could send the mails in the
database.

or should we every time transfer the flat mail files from one host to the
other if active server fails?

multi smtp for a sub domain

can somebody help me with this problem. we want to send out to our vessels on sea by ssh connections and a direct vpn sow we want to create for each *@a.vessel.com 2 smtp routes one will be our vpn the other the ssh vpn can somebody tell me where i can configure this or how i can configure this?

multi smtp relay

can somebody help me with this problem.we want to send out to our vessels on
sea by ssh connections and a direct vpnsow we want to create for each
*@a.vessel.com 2 smtp routes one will be our vpn the other the ssh vpncan
somebody tell me where i can configure this or how i can configure this?this
will need to be done for 80 vessels on the server sow I know I will need the
transport map, but as i see it I can only enter one smtp relay host there