IMAP Max Connections, DNS PTR record error

[PlayCayP]

Hello guys,

I am using the newest version of Plesk 11, running on Debian 6.0

What I would like to know is, how can I increase the max allowed connections for IMAP?
Because as soon as I add two different IMAP accounts to thunderbird, I am receiving an error, that the maximum connections have been reached.

The other thing where I need help with, is about sending mails to freenet users.

Everytime I am sending a mail to a freenet user, I receive this error:

The mail system

<MailAddressOfAnUser@freenet.de>: host mx.freenet.de[195.4.92.9] said: 550
inconsistent or no DNS PTR record for xx.xx.xx.xx(see RFC 1912 2.1) (in
reply to RCPT TO command)

Action: failed
Status: 5.0.0
Remote-MTA: dns; mx.freenet.de
Diagnostic-Code: smtp; 550 inconsistent or no DNS PTR record for xx.xx.xx.xx
(see RFC 1912 2.1)

xx.xx.xx.xx stands for my server IP.


It would be awesome if you could help me with those.

Thank you very much in advance!

 

[EgidijusS]

On redhat based systems it is in /etc/courier-imap/imapd and imapd-ssl of course same for pop3, files - pop3d and pop3d-ssl

directive - MAXDAEMONS=(number of concurrent connections)

 

[DaveKay]

Max Connections - as above.

You will need to contact your IP Address owner and ask them to create a PTR record for the IP Address that your server uses for outgoing email.

This is usually your VPS/Dedicated server host, and they should have no problem with creating/changing your PTR Record. If they do, change your host!!

This record needs to be the fully qualified domain name and should be the same as your server host name.

Have a look at http://en.wikipedia.org/wiki/Reverse_DNS_lookup for more info on PTR Records.

Most email server spam systems will do a Reverse DNS lookup when receiving email from your server. This is one way to ensure that the email message is not spam.

 

[PlayCayP]

Hello together,

thank you very much for your help!

We are using our own Rootserver, so we are the Owner of it.

You might can guide us, how to setup a Reverse DNS (PTR record) within Plesk 11?

We have created one Webspace, with one IP-Address, where a lot of different Domains and Webshops are running on.

I hope that this won't make any trouble?

Thank you in advance!

 

[Dmitriy S]

Who is provider for your domain?
Where is DNS server for this domain?
You need configure PTRrecord on this DNS server.

 

[PlayCayP]

Hello,

thank you for your message.

We got a dedicated server at LeaseWeb (NL).
The domain is running at namecheap but we have pointed the A and MX record to our IP-Address.

The DNS system at Plesk 11 (at our server where we have pointed to) is using master mode.
We have made no changes to the DNS, we have just activated it.

So does the changes need to be done within our Rootserver? (Plesk)?
If yes, which exactly settings do we need to do and where?

Thank you in advance!

 

[DaveKay]

From what you've said, it sounds like the name servers you are using are based at the domain registrar rather than on your Plesk server.

If you want to run your own name servers (ie. Using the Plesk DNS Management) you will need to create Glue Records for the domain name.

See the thread for info on Glue Records http://forum.parallels.com/showthread.php?t=281805

You can then create a PTR Record in Plesk that the internet can find.

 

[PlayCayP]

Yes, that is correct.

We are using the nameservers of namecheap.

So I will read a bit more about it and hope to get it solved somehow.

Thank you so far!

 

[DaveKay]

No probs!

Let us know if you need any further assistance!

Good luck!

 

[PlayCayP]

Hello,

I have just solved the issue by adding the PTR Record within the Control Panel of Leaseweb.
No changes of nameservers were needed.

Therefore I would like to ask you a few things:

1. Is it true that only one PTR Record can be added each IP-Address? Or is that just a restriction of the Control Panel?
2. In which case would you recommend to change the nameservers, instead of using the one of namecheap?
3. Which nameservers would you use? For example the one from google, LeaseWeb (our provider), or running an own within Plesk 11?

Thank you again!

Edit: I have just tried to send a mail to a t-online user and I received the following error:
Has it todo with any misconfiguration, on my part?

<xxxxxxxxxxxxxx@t-online.de>: host mx00.t-online.de[194.25.134.8] refused to
talk to me: 554 IP=xx.xx.xx.xx- A problem occurred. (Ask your postmaster
for help or to contact xxxx@rx.t-online.de to clarify.) (BL)

 

[DaveKay]

Run a Blacklist check on your server IP Address at www.mxtoolbox.com

 

[DaveKay]

Hello,

I have just solved the issue by adding the PTR Record within the Control Panel of Leaseweb.
No changes of nameservers were needed.

Therefore I would like to ask you a few things:

1. Is it true that only one PTR Record can be added each IP-Address? Or is that just a restriction of the Control Panel?
2. In which case would you recommend to change the nameservers, instead of using the one of namecheap?
3. Which nameservers would you use? For example the one from google, LeaseWeb (our provider), or running an own within Plesk 11?

Thank you again!

1. You only need 1 PTR Record.
2/3. It makes life simple if you are hosting websites to have Plesk handle the DNS records for you. For example, If you wanted to create subdomains on a domain, you would need to go to namecheap to create these records, where-as Plesk will do this automatically for you.

Setting up your own nameservers is fairly simple. See the thread for info http://forum.parallels.com/showthread.php?t=281805

 

[PlayCayP]

Thank you again!

I have performed a blacklist check for my server IP and it shows me two entries with a yellow exclamation mark.

SENDERBASE and SOLID

Does this mean, that I am on a blacklist? If yes, how can I get removed there? I never did anything wrong.

Regarding the PTR Record, which shall I use, if I have different domains running on same IP?

Like:
domainname1.com
domain472.de
domainabc.net

If I use:
mail.domainname1.com as the PTR Record, then I can send mails via domainname1.com

But if I would like to send a mail from domainabc.net then it won't work, because the PTR Record does not match with mail.domainabc.net?

 

[DaveKay]

In regards to being Blacklisted, you'll need to get in touch with the relevant list holders to find out their removal policies.

One tip to avoid being listed is to make sure that the setting for "what to do with mail for unknown mailboxes" is set to reject. This will stop the server from being listed for backscatter.

The PTR Record is connected to an IP address, so as long as the servers SMTP banner (Server host name) resolves to the correct IP Address, you should be able to send from any domain through your server.

 

[PlayCayP]

Do you mean this setting? (attachment).
If yes, then I am using it already.

Regarding the PTR Record, it seems that you are right

I have just entered a wrong value, before.
The default was something like hosted-by-leaseweb.com

Now I just set it to the server host name, that I am using within Plesk 11.

Thank you again for your patience !!

 

[DaveKay]

Yes, that's the setting. If your server gets a lot of emails sent to random addresses at your domains, this will stop the server sending bounces which can get you listed on the BACKSCATTER list.

Happy to help!

 

[PlayCayP]

By the way, is there any blacklist (DNS zones for DNSBL service) that you would recommend me, besides of:
ix.dnsbl.manitu.net (also called as NIXSPAM)

As I have seen there are a lot, but some of them might can block real users, that shouldnt be.

If you have any recommendation, please let me know

 

[DaveKay]

I use a large number of BL services, as part of MagicSpam, an SMTP level spam blocker. It stops most SPAM messages before they even hit the server. Not free to use though!

 

[PlayCayP]

Okay, thank you!

Until I will decide to use paid ones, are there any free ones you would use?

 

[DaveKay]

I used to use the Spamhaus lists before moving onto MagicSpam.

http://www.spamhaus.org/