Update static DNS entries every 10mins.
From MikroTik Wiki
Add a script named SMTP-Updater containting the following code:
:log info "Updating SMTP Address" :local latestsmtp :set latestsmtp [:resolve smtp.YOURUPSTREAMISP.com] :log error "Latest SMTP Address is :$latestsmtp" :local testingsmtp /ip dns static #:log info "Latest SMTP Server Address is: $latestsmtp" # Starting Loop Below: :foreach i # Add your local static DNS entries below: in=smtp.itblanket.net,smtp.saix.net,smtp.afrihost.co.za,smtp.afrihost.com do={ :set testingsmtp $i #:log info "Testing this SMTP: $testingsmtp" :if ([:len [/ip dns static find name=$testingsmtp]] >0 ) do={ #:log info "Entry exists, updating DNS" /ip dns static set [find name=$testingsmtp] address=$latestsmtp ttl=600 ; } else={ #:log info "Entry does not exist, creating the entry" /ip dns static add name=$testingsmtp address=$latestsmtp ttl=600 ; }; } #Loop ends above #:log info "Latest SMTP: $latestsmtp" :log info "Static SMTP DNS has been updated"
Now schedule it to run eg every 10 minutes.
Regards, G