Okay that exactly what I needed.
DNS A record for mail.ehowe.com will stay the same and I will change the 
A record for ehowe.com to the new IP for the webserver.

Definitely going to try the letsencrypt method vs. re-issuing my current 
certificate. Do I need to do anything there or will letsencrypt 
overwrite my current certificate?

Then after I do all this, I will have to let everyone know to change 
their SMTP, IMAP and POP hostname to mail.ehowe.com instead of their 
current value ehowe.com correct?

Thanks so much!
Randy

On 8/6/20 5:43 PM, Surgemail Support wrote:
> Change only the URL_HOST setting to mail.ehowe.com
>
> Then check the dns a entry for mail.ehowe.com points to your mail 
> servers ip address. (it looks like it does already).
>
> Then yes regenerate your ssl (use letsencrypt it's easy and free) 
> -https://surgemail.com/knowledge-base/enable-ssl/
>
> ChriSP
>
>
> On 7/08/2020 8:12 am, Randy Zumwalde wrote:
>> I need to change my Surgemail domain name from ehowe.com to 
>> mail.ehowe.com
>>
>> Currently email client's use ehowe.com as the server hostname for 
>> IMAP, POP and SMTP.
>> I need them to change that to mail.ehowe.com.
>> When I change my server hostname field in my email client to 
>> mail.ehowe.com it doesn't work. I'm guessing because the SSL 
>> certificate is for ehowe.com.
>>
>> Currently I have:
>> domain_name = ehowe.com
>> url_host = ehowe.com
>>
>> My DNS entries are
>> A record is mail.ehowe.com
>> MX record is mail.ehowe.com
>>
>> I'm not sure what to change for DNS or Surgemail and I'm afraid of 
>> messing the server up. I do know I will have to redo the SSL 
>> certificate though.
>>
>> I appreciate any insight so I don't screw my server up.
>>
>> Thanks,
>> Randy
>>