Question Mail Importing

[DennyP]

Plesk Onyx - Version 17.8.11 Update #90

I am using the Plesk Migrator to migrate sites from server1 to server2. After running the migration and testing server2, I need to refresh the mail files to pick up any new email that came into server1 while I was testing server2. Is the Domains > Mail Importing function the correct way to do this for IMAP email accounts?

1. Does the Mail Import totally replace all the mail in the IMAP accounts in server2 with the data from server1? Or does it just update server2 with changes from server1?
2. Is there a better way to refresh the email files in server2?

Once it is time to point the DNS to the new server, there will be a time when email is still going to server1 during the propagation delay period. What is the best way to get that new email on server1 to server2?

1. Should I shut off the email server on server1 so the the sender's email system will automatically retry to send the email which will eventually get to server2 when propagation of the DNS IP is completed?
2. Is there a better way to ensure no email is lost during the propagation delay interval?

Thanks for any information and suggestions. I need to make this switchover as clean as possible.

 

[menderes]

Hello @DennyP,

1. & 2. I recommend using the POP protocol. Since IMAP provides synchronization, the changes are reflected exactly. In POP, mails are downloaded and changes on server2 are not reflected on server1.

1. No, when the DNS is complete, that is, when the sender's DNS query points to server2, the mails come to server2. Resending is out of the question. Any errors in DNS settings are returned to the sender as "denied/rejected" and no resent is provided.

2. Keeping Server1 and Server2 open until all Root DNSs are updated. Because if there is no change in all of the Root DNS, the senders query the old DNS records.

 

[DennyP]

Thank you for your reply.

I can't easily use POP. I access my email from about 5 devices. They all need to share the same Inbox, Sent files, and archived folders. I didn't think POP could do that.

The reason I ask about resending is that when I send emails to some users, I will get a message back after a period of time saying that the email couldn't be delivered to the sender and it will try again in a while. I'll get another of those messages the next day. And one the following day. Then it gives up. I though the same thing might happen if the email couldn't get to my server1 while waiting on the DNS propagation to happen for them to point to server2.

In the past, when my server was down for a short time. I didn't lose any of the emails that people sent me during the outage. Once my server came back up, the emails were delivered. That is another reason I though the email system of the senders would retry if delivery failed for a while.

If I leave server1 open, I'm not sure how to get to those emails that will go to that server. I use Outlook. It uses DNS to resolve the mail server and if it is pointing to server2, it doesn't get the emails from server1. I tried using the Windows host file to control which IP Outlook uses to connect to a mail server, but Outlook appears to not use the Windows host file to resolve IP address in the testing that I have done.

 

[menderes]

If the mail server is turned off, the sending mail service will try to resend at different intervals because it cannot receive news from the remote mail server.

If the server is on but the configuration is incorrect then it rejects the mail. So the receiving server rejects the mail.

Therefore, you should not make any changes on Server1 until the DNS records are valid. (Domain name deletion etc.)

If you wish, apply a filter on server1. Send all incoming e-mails to the address you use except server2. As another solution, you can try using webmail (roundcube, horde, etc.) on server1, not Outlook for mail service on server1.

 

[DennyP]

If the mail server is turned off, the sending mail service will try to resend at different intervals because it cannot receive news from the remote mail server.

Wouldn't that be what I want to happen? I turn off the mail service on server1 after I repoint my DNS to server2 and let the sending mail service resend it until their DNS is repointed?

I thought about implementing a forwarding option on my server1 email addresses. My server1 and server2 will have the same domain names. So if I forward email from email address on server1 to the same or a different account on server2 but using the same domain name in the email address, when the DNS at server1 hasn't yet changed over to server2 won't that just forward the email back to server1?

My last resort backup plan is to use webmail from the Plesk panel on server1 since I can access Plesk by IP address instead of domain name regardless of where the DSN is pointing. But I get several hundred email a day on several accounts. I have many Outlook rules to handle many of those emails automatically. I also have a Windows anti-spam and anti-virus program that filter out those emails not caught by any of Plesk provided filters. Using Outlook is my first preference. So that is my option of last resort.

Thank you.

 

[menderes]

No,
SMTP 421 or 441 error codes work when the receiving server is unreachable. According to these error codes, the sender will try to send again at different intervals. The thing to note here is that if the sender sees the records (MX) of the e-mail address on server1, the re-sending process is made to server1's ip address. Because the SMTP protocol works with helo-ehlo and the hostname must be resolved.

IP addresses return all e-mail related error codes. Therefore, closing server1 will not be the solution. If you also move server1's ip address to server2, it might be the solution you mentioned.

 

[DennyP]

Thank you for the clarification on the resending based on the MX records. Since those won't change on server1, the resending will still go back to server1. That option is eliminated.

I can't easily move server1's IP to server2 because of the hosting company restrictions on IP addresses. The servers are in different physical locations behind different routers, etc.

But I think I have another plan. Please pick holes in it, if there are any.

I currently have 2 other domains on server2 whose DNS NS pointers already point to server2 and have been pointing there for a couple of weeks. So all the propagation on those should be done. I can define email addresses on one of those other domains to correspond to the same email names on server1. Then I can do a forward on the server1 email addresses to the same user (different domain) on server2. I can define those server2 accounts in Outlook and let Outlook handle the incoming email on those forwarded accounts. Outlook will do the spam and virus filtering leaving just valid emails. Once my ISP has propagated the DSN change, I can run rules in Outlook to resend the emails from the mirrored accounts back to their normal accounts. Seems doable?

Thanks for reviewing that plan.

 

[menderes]

Yes, you can do as you mentioned. You can forward all mails on server1 to the mail address on server2 with different domains. The rules you have already created in Outlook look at the incoming e-mail address. If not, you can export all Outlook rules and import them later.

Good luck with.

 

[DennyP]

Thank you for reviewing that. Outlook lets me take a rule for one account and save it in another account. So copying them will be easy. Since I am using a different domain name that has already been propagated, I can test this all out ahead of time. I just will adjust the rules on the mirror domain slightly to not actually send the emails back to where they came from so I don't get duplicates. I will try to remember to report back here how that testing goes. I will also try to remember to report back here how the "go live" went (or didn't go). But don't hold your breath. I have until the end of November before my server1 goes away. But I'd like to be converted by the end of October to allow some wiggle room.

Thanks again.