MailMarshal uses de server.domain.com for it’s Helo name. You will probably name your server after it’s role, so this can be for expample mailmarshal01.domain.local. But is most cases you use an other external mx record name. therefor you can change this setting from within MailMarshal.
This is a MailMarshal Node-specific setting, and it may be necessary to configure each node as desired.
- Open MailMarshal Configurator.
- Select Server and Array Configuration.
- Select the desired node or server name.
- Right-click on the server name and select Properties.
- Enter the desired HELO name under Advanced | Server Host Name.
Now if you telnet you server from the internet on port 25 you will see the correct name in the welcome string.
source: MailMarshal.com