Seemingly random official mail being rejected

[Stephanjansen]

Good day

My ISP hosts a pop spooling account for when my mail server goes down my mail gets cached with them till my server gets back up . . . then I have my PROXMOX box forwarding to my mail to my mail server.

My issue is that my caching mail box receives mail that is seemingly being rejected from my PROXMOX box? PLEASE HELP!!

 

[martin]

Good day

My ISP hosts a pop spooling account for when my mail server goes down my mail gets cached with them till my server gets back up . . . then I have my PROXMOX box forwarding to my mail to my mail server.

My issue is that my caching mail box receives mail that is seemingly being rejected from my PROXMOX box? PLEASE HELP!!

Hi Stephan,

Why are the emails rejected, please see the log files for the reason. what license do you use?

 

[Stephanjansen]

random official mail being rejected

Hi Admin here is a peace of the log. . . how do i add a "QUEUE" it seems there is "NOQUEUE"


postfix/smtpdNOQUEUE: reject: RCPT from ctb-mesg-2-1.saix.net[196.25.240.86]: 450
4.7.1 <Lindsay@george.org.za>: Recipient address rejected: Service is
unavailable (try later); from=<uhamgeo@intekom.co.za>
to=<Lindsay@george.org.za> proto=ESMTP helo=<ctb-mesg-2-1.saix.net> proxpolicydefer greylisted mail postfix/smtpdconnect from ctb-mesg-2-1.saix.net[196.25.240.86] postfix/smtpddisconnect from smtplink.lionsure.com[196.25.20.2] postfix/smtpdNOQUEUE: reject: RCPT from smtplink.lionsure.com[196.25.20.2]: 450
4.7.1 <Zoleka-h@george.org.za>: Recipient address rejected: Service
is unavailable (try later); from=<ayanda.ngqeza@lionsure.com>
to=<Zoleka-h@george.org.za> proto=ESMTP helo=<smtplink.lionsure.com>

 

[Stephanjansen]

random official mail being rejected

I'm running a trail with 16 days left . . . I'm waiting for the "ok" from my boss to buy the LIC / software. But he wants to see the Server in action . . .

 

[dietmar]

Please add the IP address of the backup MX (spooling host) to your greylist exclusion (Configuration/System/MailProxy/Greylist excl.)

- Dietmar

 

[Stephanjansen]

random official mail being rejected

Same error . . . Please advise?

 

[tom]

Same error . . . Please advise?

Hi,

the log entry from proxmox:
_
Recipient address rejected: Service is unavailable (try later)
_

means that greylisting is active. please see this for a basic explanation what greylisting is doing.

as it does not make sense to greylist your ISP, as you really want emails from him, you have to exclude the ISP. so you have to exclude the IP from greylisting. please take a deeper look into the log file an compare the greylisted ip to the one you added to the greylist exclusion.

Maybe the problem here is, that the ISP use more than one IP addresses - so you have to add all to the exclusion list - ask your ISP.

To test without greylisting: you can globally disable greylisting.

Now, I am going deeper into your setup, I see you have two MX records:

george.org.za.MXIN86400mail.george.org.za. [Preference = 10] george.org.za.MXIN86400mx2.mweb.net. [Preference = 20] george.org.za.NSIN86400ns2.mweb.co.za. george.org.za.NSIN86400ns1.mweb.co.za. mail.george.org.za.AIN86400196.211.48.218 mx2.mweb.net.AIN300196.2.16.215 ns1.mweb.co.za.AIN2800196.2.16.3 ns2.mweb.co.za.AIN2800196.2.46.254

if I connect to 196.211.48.218 on port 25, a groupwise server is answering. if I connect to 196.2.16.215, an exim mail server is answering, seems your ISP. where is proxmox?

 

[Stephanjansen]

I am running a live mail server "200 users" so i can not afford being off line . . when i implement the PROXMOX BOX "I'm off line" some mail, not all mail gets rejected, SPAM and official mail alike . . . My male server is a Novell 6.5 BOX. I will enable the PROXMOX BOX from Now till 1:00PM +2 GMT South Africa. Please do some test and advise? Thank you for the help.

 

[Stephanjansen]

random official mail being rejected

Ok . . .it's 1:00pm. I need to switch back now. I got 55 incoming mails of witch 29 was Junk and about 41 was rejected . . .

 

[tom]

Ok . . .it's 1:00pm. I need to switch back now. I got 55 incoming mails of witch 29 was Junk and about 41 was rejected . . .

Hi,

whats the results of testing? what are the logs saying? maybe you can send the following to support@proxmox.com:

- backup of your config (configuration/system/backup)
- the file /var/log/syslog

 

[Stephanjansen]

So i switched off the "Use Greylisting and Use SPF" options, it looks like the mail is being delivered now. How will this affect my Anti SPAM server's POTENCY.





"

 

[tom]

So i switched off the "Use Greylisting and Use SPF" options, it looks like the mail is being delivered now. How will this affect my Anti SPAM server's POTENCY.





"

Hi,

As i wrote, you have to exclude your ISP from greylisting, then you should enable it to get best results. Greylisting reject unwanted emails on smtp level and this is very effective agains spammer and botnets. Most Emailservers can reject more than 50 % of emails by doing this.

You should also note, that greylisting does not produce errors, it just says to unknown sender that proxmox is temporäre unavailable. If the sender tries the connection again (RFC conform), Proxmox accepts the email and adds the sender to a internal whitelist. also if a sender has a valid SPF record, he is never greylisted.